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.
Any chemical compound, mixture, or device that functions by explosion.
a single chemical compound that can produce an explosion.
A canine trained to detect and alert to the presence of explosives and explosives related substances (e.g., propellants, oxidizers, precursors) for which it has been trained that may be located in the environment.
A canine trained to detect and alert to the presence of explosives and explosives related substances (e.g., propellants, oxidizers, precursors) for which it has been trained that may be located in the environment and/or person borne.
Study of how chemistry, physics, fire science, engineering disciplines of fluid and solid mechanics, and heat transfer interact to influence explosion behavior.
Study of how chemistry, physics, fire science, engineering disciplines of fluid and solid mechanics, and heat transfer interact to influence explosion behavior.
Any material that can act as fuel for an explosion.
a mixture of separate fuel and oxidizer components that together can produce an explosion.
the detection, identification, on-site evaluation, rendering safe, recovery, and final disposal of unexploded explosive ordnance; it may also include explosive ordnance which has become hazardous by damage or deterioration.
A chemical substance that can be utilized in the production of explosives by either mixing or blending with other substances, or by chemical processing. The vast majority of chemicals are used for legitimate purposes. However, some chemicals could potentially be misused for the illicit manufacture of homemade or improvised explosive. Indeed, relatively small amounts of select chemicals can be applied in certain processes that produce a significant amount of explosives.
material remaining from an explosive deagration or detonation or from direct contact withan explosive. Explosive residue generally does not have adiscernible morphology, can be visible or non-visible, and cancontain uninitiated and post-combustion components.3.2.1.1 DiscussionVisible explosive residue can be pres-ent in large (grams) and small (single particle or single crystal)quantities.
Material remaining from an explosive deflagration or detonation or from direct contact with an explosive. Explosive residue generally does not have a discernible morphology; can be visible or non-visible; and can contain uninitiated and post-combustion components.
an arrangement of explosive components by which the initial force from the primer is transmitted and intensified until it reaches and detonates the main explosive composition.
See download
See download
The side of a structural assembly or object that is directly exposed to the fire.
The parameter, associated with the assessment method used, that characterizes the dispersion of the values that could reasonably be attributed to the measurand.
File system typically used with Linux-based operating systems
An evaluation of practitioner performance against pre-established criteria by means of interlaboratory comparisons. [ISO/IEC 17043:2010]
The condition in which a birefringent particle appears dark when viewed between crossed polarizers
the condition in which a birefringent particle appears dark when viewed between crossed polarizers.
A procedure where the reinforcement of a previously reinforced behavior is discontinued with the intention to reduce the occurrence of that behavior
To cause to cease burning.
Any method of exporting data from a source
Any method of exporting data from a source.
any plot of signal intensity observed at a chosen m/z value or set of values in a series of mass spectra recorded as a function of time.
any plot of signal intensity observed at a chosen m/z value or set of values in a series of mass spectra recorded as a function of time. Definitions of Terms Relating to Mass Spectrometry (6)
Material originating from a source other than the specimen (synonyms: contaminant and foreign material)
Material originating from a source other than the specimen
Material originating from a source other than the specimen
An estimation of a drug concentration (e.g., ethanol) at a time other than the time of sample collection. There are two types of extrpolation: back [retrograde] and forward [anterograde] extrapolation
A class of smokeless powders produced by an extrusion process where the final grain morphologies are disc or cylinder
Organization responsible for recovering corneas/eyes from donors.
In textiles, a planar structure consisting of yarns or fibers
in textiles, a planar structure consisting of yarns or fibers.
In facial identification, the automated determination of the presence of human faces in digital images
In facial identification, the automated determination of the presence of human faces in digital images.
In facial identification, (1) by automated systems, the automated searching of a facial image as a probe in a facial recognition system (one-to-many), typically resulting in a group (candidate list) of facial images being returned to a human operator in ranked order based on system-evaluated similarity; (2) by humans, the mental process by which an observer identifies a person as being one they have seen before
In facial identification,(1) by automated systems, the automated searching of a facial image as a probe in a facial recognition system (one-to-many), typically resulting in a group (candidate list) of facial images being returned to a human operator in ranked order based on system-evaluated similarity; (2) by humans, the mental process by which an observer identifies a person as being one they have seen before.
An investigative technique combining anatomical knowledge, artistic capability, and forensic anthropological evidence to render an estimate of an individuals facial appearance in life.
In facial identification, a manual process to identify similarities or dissimilarities between two (or more) facial images or facial image(s) and a live subject for the purpose of determining if they represent the same person or different person
In facial identification, a manual pro- cess to identify similarities or dissimilarities between two (or more) facial images or facial image(s) and a live subject for the purpose of determining if they represent the same person or different person.
Gross features considered in virtually all comparisons
Gross features considered in virtually all comparisons
In facial identification, a formal systematic facial comparison
In facial identification, a formal sys- tematic facial comparison.
The discipline of image-based comparisons of human facial features
The discipline of image-based comparisons of human facial features
In facial identification, the process of collecting a biometric sample from an individual by means of a sensor