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.
See heat release Rate (HRR).
in image analysis, a digital camera or scanner file format, usually proprietary, for minimally processed digital image data.
Ordinate values that come directly from the instrument which have not been manipulated (e.g.,trimmed, filtered, and/or interpolation applied).
A family of file formats, often specific to different models of digital imageryequipment, that are not yet processed for storage in a 'printable' image format such asJPEG or TIFF. The file extension '.raw' is only one such format.
thin oblong crystals with length about twice the width, resembling a safety razor blade.
Royal Canadian Mounted Police.
a type of permanent data storage (memory) that can be read but not altered by the system.
Discussion—Data stored in read-only memory is not affected by power loss to the system.
A chemical used to react with another chemical, often to confirm or deny the presence of the second chemical.
a chemical used to react with another chemical, often to confirm or deny the presene of the second chemical.
A sample that contains no analyte, but contains the buffer, test reagents, or other materials required to perform a particular test. This is a negative control where results are not expected. The observation where the result(s) in this control may indicate the presence of contaminated or compromised reagents, which may impact the DNA or the serological results observed from samples tested at the same time. For forensic DNA testing this control is treated the same as, and parallel to, the DNA samples being analyzed.
A verbal command given to the canine, terminating with the canine returning to the canine handler. The canine's response to return to the canine handler on command.
The recall rate is also known as true positive rate. It is defined as the number (or percentage) of toolmark specimens containing a Known-Match in the test set for which a Known-Match is correctly determined.
The document or other substrate that received indentations, other paper fiber disturbances, or other markings.
A document that is similar in content and structure to a code or standard but that contains only nonmandatory provisions using the word 'should' to indicate recommendations in the body of the text.
process of repairing damaged media to allow the retrieval of data.
Document with observations, statements of results achieved, or evidence of activities performed.
A defined set of fields that contain data as defined in this standard.
The act of converting an acoustic voice signal directly from an individual into a storagemedia, perhaps through contemporaneous, intermediate (transient) signal types. Note:This definition is retained because of its entrenchment in natural language use.Consequently, a record (n) is not recorded, it is created. Transcoding is the term usedfor further processing of the voice signal and any digital or analog representation of thatsignal.
The act of creating a record contained in an ANSI/NIST-ITL transaction.
A record/log in the use of a trained canine team in an operational environment, as opposed to training records. A log constituting a piece of evidence about the past, especially an account of an act or occurrence kept in writing or some other permanent form, i.e., electronic format. (See deployment record or utilization record.)
Objective evidence of a condition, result, work performed, activity conducted, and/or quality of asystem or process for archival purposes.
chemical, term used in analytical and preparative chemistry to denote the fraction of the total quantity of a substance recoverable following a chemical procedure.
Over-writing of segments of a voice signal for the purpose of masking speech content ina way that does not disrupt the time record of the original recording.
Data derived from biological specimens of a known individual.
Data generated from a reference sample.
The assembly of data related to a specific identifiable human group comprising all the relevant information to enable dental age assessment.
A collection of reference material or sequences assembled for use in comparative analyses for purposes of taxonomic identification, individual source evaluation, population assignment, or mitotyping.
A reference measurement of a flat surface (e.g., mirror) which includes the errors and opticalaberrations of the measurement system. This data file can be stored and subtracted from allsubsequent measurements.
A sample of a population used in a method.
an ignitable liquid used for comparison with case data for classification purposes.
Discussion—Reference ignitable liquids can be obtained from a variety of sources, due to the large range of applications of ignitable liquids.
Material, sufficiently homogenous and stable with respect to one or more specified properties, which has been established to be fit for its intended use in a measurement.
Material, sufficiently homogenous and stable with reference to specified properties, which have been established to be fit for its intended use in a measurement or in examination of nominal properties.
Biological specimens of known identity or data derived from them, or from published sources. Voucher specimens are a subset of reference material (see voucher specimen).
material, sufficiently homogeneous and stable with respect to one or more specified properties, which has been established to be fit for its intended use in a measurement processj
j: Joint Committee for Guides in Metrology (JCGM), International vocabulary of metrology - Basic and general concepts and associated terms (VIM) (Sèvres, France: International Bureau of Weights and Measures [BIPM]- JCGM 200) available at https://www.bipm.org/en/publications/guides.
Material, sufficiently homogeneous and stable with reference to specified properties, which has been established to be fit for its intended use in a measurement or in examination of nominal properties.
Biological specimens of known identity or data derived from them, or from published sources. Voucher specimens are a subset of reference material (see voucher specimen).
Biological specimens of known identity or data derived from them.
Biological specimens, materials or substances of known identity and verified properties, or data derived from them.
Biological specimens, materials or substances of known identity and verified properties, or data derived from them.
material from a known source used for comparison purposes in a forensic process.
Discussion—(1) This includes biological material taken from a person (for example, hair, blood, saliva), and non-biological material (for example, carpet, paint, fabric). (2) A reference sample can be taken from an item to ensure the substrate has no adverse effect on the performance of the test. (3) A reference sample can be used to address the question of the source of an unknown sample, one would compare the unknown sample with a reference sample.
Biological material obtained from a known individual and collected for the purpose of comparison to evidentiary sample(s).
Biological material obtained from a known individual and collected for purposes of comparison to evidentiary samples.
Samples of known origin collected for purposes of comparison to samples of unknown origin.
Samples of known origin collected for purposes of comparison to samples of unknown origin.
Measurement standard that is used to calibrate or verify (working reference standard) measuring instruments or measuring systems.
A detailed investigation and analysis of a specific population to relate chronologic age to dental development and maturation.
the ratio of the velocity of light in a vacuum to the velocity of light in some medium.
A lack of response on the part of the canine, or a declination to accept instruction or direction.