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.
spectral artifacts that result from the production of characteristic X-rays from structural components of the XRF instrument.
peaks that can occur in the X-ray spectrum as a result of interaction of the electron beam or fluorescent radiation with components of the scanning electron microscope itself.
in computer forensics, the time generated by the system clock and used by the operating system.
A method that employs a specific search sequence to increase accuracy and minimize omissions, while maximizing coverage. Such patterns usually have set start and stop points.
plates with appreciable thickness but less than the length or breadth.
property of an adhesive that allows it to form a bond immediately with a surface with the application of only slight pressure.
low molecular weight organic material that is added to the adhesive base polymer to impart tack.
solid resins added to the adhesive base polymer to impart the necessary tack and adhesion.
Any reward perceptible by touch for the canine.
Chemical markers (e.g., Nitro compounds) that vaporize rapidly and are added to enhance the detection of plastic explosives by instrumental analysis.
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.
Nitro compounds that possess a high vapor pressure and are added to enhance the detection of plastic explosives by vapor detection means.
Acronym for Toe and foot print Acquisition Profile. It is a series of sets ofprogressively more stringent parameters and requirements relevant to plantar printacquisition
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
the study of the processes affecting remains after death.
the study of the processes affecting remains after death.
The scent for which the canine is trained to respond.
The scent for which the canine is trained to respond.
The scent for which the canine is trained to respond. NOTE: In patrol detection work the term "decoy" if often used.
The odor/scent for which the canine is trained to respond. (See source).
an analyte of interest to the analyst.
an analyte of interest to the analyst.
A fuel that is subject to ignition by thermal radiation such as from a flame or a hot gas layer.
A diagnostic ion used for comparing relative intensities of other monitored ions when calculating ion ratios.
A person bearing an explosive, or explosive precursor chemicals.
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.)
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.)
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.)
A pathway that was laid by a target subject that matches the scent article presented to the canine. (See matching scent trail.)
The process of conditioning an animal to touch a particular object.
A specific job behavior or activity.
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.[
Literature references accepted by the relevant scientific community and providing the classification of species for a group of organisms.
Literature references accepted by the relevant scientific community and providing the classification (e.g. family, genus, species) for a group of organisms.
Analyses to establish the taxonomic classification of the sample. These analyses are based on class characters diagnostic for the taxonomic level in question.
The classification of an organism to family, genus, species, etc. These analyses are based on class characters diagnostic for the taxonomic level in question
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.
The science of identifying and naming species with the intent of arranging them into a classification.
The designated individual in the laboratory who has technical responsibility.
The designated individual in the laboratory who has technical responsibility.
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.
An employee who is accountable for the technical operations of the laboratory and who is authorized to initiate, suspend, and resume laboratory operations.
Written documentation maintained by the laboratory including laboratory policies, technical protocols and methods for specific forensic analyses (see also standard operating procedure).
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.
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.
a qualified second party’s evaluation of reports, notes, data, and other documentation to determine there is appropriate and sufficient support for the actions, results, conclusions, opinions, and interpretations.
Used to describe the type of forensic DNA analysis performed in the laboratory, such as SNP, STR, YSTR, or mitochondrial DNA.