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OSAC Lexicon

The OSAC Lexicon is a compendium of forensic science terms and definitions. This terminology tool was created to help bring consistency and understanding to the way terms are used by the various forensic science. Use of the OSAC Lexicon does not replace the need to reference the original published source.

The terms and definitions in the OSAC Lexicon come from the published literature, including documentary standards and technical reports. It is continually updated with the latest work from OSAC units, as well as terms from newly published documentary standards and standards elevated to the OSAC Registry.

Gradually terms are evaluated and harmonized by the OSAC to a single term. This process results in an OSAC Preferred Term. An OSAC Preferred Term is a term, along with its definition, that has undergone review and evaluation by the FSSB Terminology Task Group and has been approved by the FSSB. The FSSB recommends that subcommittees use OSAC Preferred Terms when drafting standards.

The OSAC Lexicon should be the primary resource for terminology and used when drafting and editing forensic science standards and other OSAC work products

Searches term, definition, and source for any of these keywords.
Searches term name.
Searches standard designation number.
Displaying 3101 - 3150 of 3437

Chemical markers (e.g., Nitro compounds) that vaporize rapidly and are added to enhance the detection of plastic explosives by instrumental analysis.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

a chemical marker or physical multilayer chip incorporated into an explosive material that may be recovered post-blast, enabling the identification of the manufacturer and the date and time of production.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

Nitro compounds that possess a high vapor pressure and are added to enhance the detection of plastic explosives by vapor detection means.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 092 Standard for Training and Certification of Canine Detection of Explosives. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Tires set immediately one behind the other.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Acronym for Toe and foot print Acquisition Profile. It is a series of sets ofprogressively more stringent parameters and requirements relevant to plantar printacquisition

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

All of the processes resulting in the decomposition of organic material. Also pertains to the study of the processes affecting remains between death and discovery

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 028 Wildlife Forensics Morphology Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

the study of the processes affecting remains after death.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

the study of the processes affecting remains after death.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E3392-24 Standard Guide for Forensic Physical Fit Examination. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428 , 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

The study of the processes affecting remains after death.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 149 Standard for Taphonomic Observations in Support of the Postmortem Interval. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2022. Source link

A surface onto which blood has been deposited.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 033, Terms and Definitions in Bloodstain Pattern Analysis Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

The odor/scent for which the canine is trained to respond. (See source).

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

The scent for which the canine is trained to respond. NOTE: In patrol detection work the term "decoy" if often used.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 027 Standard for Training and Certification of Canine Detection of Humans: Patrol Canine Team. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The scent for which the canine is trained to respond.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 026 Standard for Training and Certification of Canine Detection of Humans: An Aged Trail Using Pre-scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The scent for which the canine is trained to respond.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 024 Standard for Training and Certification of Canine Detection of Humans: Location Check Using Pre‐scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

an analyte of interest to the analyst.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

an analyte of interest to the analyst.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E3197-23 Standard Terminology Relating to Examination of Fire Debris. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2023. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

A fuel that is subject to ignition by thermal radiation such as from a flame or a hot gas layer.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2021 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2021. Source link

A specific set of friction ridge features selected as a starting point during comparison.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 166 Best Practice Recommendation for Comparison and Evaluation of Friction Ridge Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link

A diagnostic ion used for comparing relative intensities of other monitored ions when calculating ion ratios.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 098 Standard for Mass Spectral Analysis in Forensic Toxicology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2023. Source link

A person bearing an explosive, or explosive precursor chemicals.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 092 Standard for Training and Certification of Canine Detection of Explosives. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

A pathway that was laid by a target subject that matches the scent article presented to the canine. (See matching scent trail.)

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

A pathway that was laid by a target subject that is associated with the scent article presented to the canine. (See 3.9 associated scent trail.)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 027 Standard for Training and Certification of Canine Detection of Humans: Patrol Canine Team. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

A pathway that was laid by a target subject that is associated with the scent article presented to the canine. (See 3.9 associated scent trail.)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 026 Standard for Training and Certification of Canine Detection of Humans: An Aged Trail Using Pre-scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

A pathway that was laid by a target subject that is associated with the scent article presented to the canine. (See 3.9 associated scent trail.)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 024 Standard for Training and Certification of Canine Detection of Humans: Location Check Using Pre‐scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The process of conditioning an animal to touch a particular object.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

A specific job behavior or activity.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 1033:2022 Standard for Professional Qualifications for Fire Investigator. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2022. Source link

An indelible image on the skin that was applied to the skin. [2015a>] This is thedefinition of tattoo as used in Field 10.003: Image type / IMT.Field 10.042: SMT descriptors / SMD breaks this down into subsets, one of which is also called tattoo. See Table 71 Type-10 image types for more detail.[

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Literature references accepted by the relevant scientific community and providing the classification (e.g. family, genus, species) for a group of organisms.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 047 Wildlife Forensics Validation Standard - Validating New Primers for Sequencing. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Literature references accepted by the relevant scientific community and providing the classification of species for a group of organisms.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 019 Wildlife Forensics General Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

The classification of an organism to family, genus, species, etc. These analyses are based on class characters diagnostic for the taxonomic level in question

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 047 Wildlife Forensics Validation Standard - Validating New Primers for Sequencing. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Analyses to establish the taxonomic classification of the sample. These analyses are based on class characters diagnostic for the taxonomic level in question.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 019 Wildlife Forensics General Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Analyses to establish the classification of biological evidence to family, genus, species, etc. These analyses are based on class characters (e.g., morphological, genetic) that are diagnostic for the taxonomic level in question.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 180-24 Standard for the Selection and Evaluation of GenBank® Results for Taxonomic Assignment of Wildlife . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

Analysis to establish the classification of an organism to family, genus, species, etc. This analysis is based on class characters diagnostic for the taxonomic level in question.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 106 Wildlife Forensics—Protein Serology Method for Taxonomic Identification. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2020. Source link

Analyses used to establish the classification of an organism to family, genus, species, etc. These analyses are based on characters (e.g. morphological or genetic) diagnostic for the taxonomic level in question.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 048 Wildlife Forensic DNA Standard Procedures. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

The science of identifying and naming species with the intent of arranging them into a classification.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 028 Wildlife Forensics Morphology Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Fractures that have occurred in footwear outsoles or tire treads that reflect irregular edges. Tears are randomly acquired characteristics.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

The designated individual in the laboratory who has technical responsibility.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 110 Standards for Training in Forensic Serological Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

The designated individual in the laboratory who has technical responsibility.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 077 Standard for the Developmental and Internal Validation of Forensic Serological Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

a bundle of natural fibers (for example, hemp, jute, and sisal) composed of individual elongated cells that can be physically or chemically separated and examined microscopically for identifying characteristics.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

An employee who is accountable for the technical operations of the laboratory and who is authorized to initiate, suspend, and resume laboratory operations.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 123 Standard for Routine Internal Evaluation of a Laboratory’s DNA Interpretation and Comparison Protocol. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link

Written documentation maintained by the laboratory including laboratory policies, technical protocols and methods for specific forensic analyses (see also standard operating procedure).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 019 Wildlife Forensics General Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

A qualified second party's evaluation of reports, notes, data, and other documentation to ensure there is appropriate and sufficient support for the actions, results, conclusions, opinions, and interpretations.  

Also referenced in ANSI/ASB 019 Wildlife Forensics General Standards, ANSI/ASB Technical Report 025, Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions, ANSI/ASB 063 Implementation of 3D Technologies in Forensic Firearm and Toolmark Comparison Laboratories, ANSI/ASB 142-22 Best Practice Recommendations for the Resolution of Conflicts in Friction Ridge Examination, ANSI/ASTM E3392-24 Standard Guide for Forensic Physical Fit Examination, ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, ANSI/ASB Standard 099 Standard for Footwear/Tire Examination Proficiency Testing Program, ANSI/ASB 168 Standard for Testimony Monitoring in Friction Ridge Examination, ANSI/ASB 143 Standard for Technical Review in Friction Ridge Examination

Date Added to Lexicon
Committee Source
FSSB

An individual with the knowledge/expertise to conduct the technical review to determine if theappropriate examinations have been performed, support the results/conclusions of thedevelopment and/or deployment validations, and that the reported results are consistent with therecorded data and are within the scope of testing.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 063 Implementation of 3D Technologies in Forensic Firearm and Toolmark Comparison Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Used to describe the type of forensic DNA analysis performed in the laboratory, such as SNP, STR, YSTR, or mitochondrial DNA.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 022 Standard for Forensic DNA Analysis Training Programs. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

the resting phase of the hair follicle in the hair growth cycle.
Discussion—During this phase, the hair has stopped growing and the root becomes keratinized and bulbous (club-like) in shape.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

The general consistence with which the animal behaves. Broad classes of temperament appear to be heritable. OutgoingBehavior of the canine characterized by seeking human interaction. StableBehavior of the canine that is consistent over time, place and environmental conditions.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

The general consistence with which the animal behaves. Broad classes of temperament appear to be heritable. OutgoingBehavior of the canine characterized by seeking human interaction. StableBehavior of the canine that is consistent over time, place and environmental conditions.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 085 Standard for Detection Canine Selection, Kenneling, and Healthcare. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The degree of sensible heat of a body as measured by a thermometer or similar instrument.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2021 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2021. Source link

in facial identification, a set of biometric measurement data prepared by a facial recognition (FR) system from a facial image.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

The quality of a canine to persist at a task regardless of the environmental distractions or task difficulty.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
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