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.
Type II Error
Ultimates
Ultraviolet (Uv)
Electromagnetic radiation with a wavelength from 100 nm (30 PHz) to 380 nm (750 THz), which, when used as a light source, can fluoresce dental materials for better visualization and location.
ultraviolet (UV)
Referring to radiant flux having wavelengths shorter than the wavelengths of light, usually wavelengths from about 10 nm to 380 nm.
Unallocated Space
Unconditioned Response Unconditioned Stimulus
See classical conditioning.
Unconfirmed Alert
An alert for which the presence of a trained odor/scent cannot be confirmed. This may be the result of residual or lingering odor/scent that the canine can detect but which has not been confirmed by technology or direct observation. (See non-productive response.)
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s).
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s).
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s).
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s)
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s)
Unconfirmed Operational Outcome
Lack of verification of search results following a deployment of a canine team(s)
Uncontrolled Image, Ad Hoc Image
Understanding Or Agreement
A written or oral consensus between the interested parties concerning the management of the investigations.
undetermined (manner of death)
Manner of death used when the information pointing to one manner of death is no more compelling than another after thorough consideration of all available information.
uniaxial
an anisotropic crystal in the tetragonal or hexagonal system having one optic axis (isotropic direction) and either two (tetragonal) or three (hexagonal) directions which are alike and perpendicular to the direction of the optic axis.
Unicode
A computing industry standard for the representation of most of the world's scripts (suchas Latin letters, Cyrillic letters, Chinese characters, special symbols and others). See A.
uninformative
A scenario where the laboratory has concluded that the data do not support or refute a proposition as defined by the laboratory and based on validation studies.
uninterpretable
The inability to use results for comparisons due to poor or limited data quality.
Unit Cell
Unit Outsole
universal precautions
Measures taken to ensure safety under the assumption that any unknown materials or situations present the most dangerous scenario possible.
Unsuitable for Comparison
Data that cannot be used for comparisons for reasons including, but not limited to, poor or limited data quality, mixture complexity, or a failure to meet quality assurance requirements.
Unsuitable For Comparison
Data that cannot be used for comparisons for reasons including, but not limited to, poor or limited data quality, mixture complexity, or a failure to meet quality assurance requirements.
unsuitable for comparison
Data that cannot be used for comparisons for reasons including, but not limited to, poor or limited data quality, mixture complexity, or a failure to meet quality assurance requirements.
Unsuitable for Interpretation/comparison
Data that cannot be used for interpretation/comparison for reasons including, but not limited to, poor or limited data quality, mixture complexity, or a failure to meet quality assurance requirements based on developmental validation studies, the laboratory’s internal validation studies, and the laboratory’s documented and verified interpretation and comparison protocol.
Unvulcanized/Raw Rubber
Upper
Upper Layer
A buoyant layer of hot gases and smoke produced by a fire in a compartment.
Upper Limit of Quantitation (ULOQ)
highest concentration of an analyte in a sample that can be reliably measured with acceptable bias and precision
Upper Limit Of Quantitation (Uloq)
The highest concentration of an analyte in a sample that can be reliably measured with acceptable bias and precision
Urban Search
To locate target odor/scent sources in a city type of environment.
Urine Specific Gravity
A measure to determine the concentration of the urine.
Urine Specific Gravity
A measure to determine the concentration of the urine.
Urine Specific Gravity
Uniform Resource Identifier.
URL
Uniform Resource Locator.
USB
Universal Serial Bus. Refers to a family of standardized computer peripheral interfaces.
UTC
Coordinated Universal Time.
UTF
Unicode Consortium Standard Transmission Format
utility decision
A decision made by an examiner in accordance with FSP policy and/or procedure as to whether or not an impression will proceed to the next step in the examination process.
UVIS/ UDIM
The Unified Victim Identification System developed by the Office of the Chief MedicalExaminer of New York City and its built-in Dental Identification Model.
V-Pattern
V-shaped patterns are created by flames, convective or radiated heat from hot fire gases, or smoke within the fire plume. The V pattern often appears as lines of demarcation.
Vaccination
The administration of antigenic material (a vaccine) to stimulate an individual's immune system to develop adaptive immunity to a pathogen. Vaccines can prevent or ameliorate morbidity from infection. (See immunize.)
Vaccination
The administration of antigenic material (a vaccine) to stimulate an individual's immune system to develop adaptive immunity to a pathogen. Vaccines can prevent or ameliorate morbidity from infection.
Vaccine Titer
The antibody titer is a test that detects the presence and measures the amount of antibodies within a canine's blood. The amount and diversity of antibodies correlates to the strength of the body's immune response.
Vaccine Titer
The antibody titer is a test that detects the presence and measures the amount of antibodies within a canine's blood. The amount and diversity of antibodies correlates to the strength of the body's immune response.
Validation
OSAC Preferred
A process of evaluating a system, method, or component, to determine that requirements for an intended use or application have been fulfilled.
Also referenced in ANSI/ASB Technical Report 025, Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions, ANSI/ASB 018 Standard for Validation of Probabilstic Genotyping Systems, ANSI/ASB 020 Standard for Validation Studies of DNA Mixtures, and Development and Verification of a Laboratory's Mixture Interpretation Protocol, ANSI/ASB 038 Standard for Internal Validation of Forensic DNA Analysis Methods, ANSI/ASB 019 Wildlife Forensics General Standards, ANSI/ASB 047 Wildlife Forensics Validation Standard and Validating New Primers for Sequencing, ANSI/ASB 022 Standard for Forensic DNA Analysis Training Programs, ANSI/ASB 063 Implementation of 3D Technologies in Forensic Firearm and Toolmark Comparison Laboratories, ASTM E1732 Standard Terminology Relating to Forensic Science, ANSI/ASB Standard 072 Standard for the Validation of Procedures in Bloodstain Pattern Analysis, ANSI/ASB 046 Wildlife Forensics Validation Standards—STR Analysis.
Also referenced in ISO/IEC 17025:2017 General Requirements For The Competence Of Testing And Calibration Laboratories. International Organization for Standardization/International Electrotechnical Commission, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2017.
Validation Review
A review used to determine the limitations of the method/procedure; conditions under whichreliable results can be obtained; critical aspects of a procedure/method that must be controlled andmonitored; and the scope and accuracy of the procedure to meet the needs of a given application.
Validity
The extent to which a measurement actually measures what you intend to measure which provides information relevant to the questions asked; valid measures provide a good, close relationship between a variable. Validity has two aspects: accuracy and specificity.