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.
An arc site where one or more of the circuit conductors were physically severed by the arcing event at that location.
The portion of the hair emerging from the hair follicle.
the portion of the hair emerging from the hair follicle.
The shape of the hair both longitudinally (for example, curly, straight) and cross-sectionally (for example, round, flattened).
the shape of the hair both longitudinally (for example, curly, straight) and cross-sectionally (for example, round, flattened).
The diameter of the hair. DiscussionThis is expressed either numerically or in relative terms, such as fine, medium, or coarse.
the diameter of the hair.
Discussion—This is expressed either numerically or in relative terms, such as fine, medium, or coarse.
Indicates a mandatory requirement.
Used to indicate that a provision is mandatory. (unless otherwise documented for non-compliance).
An explosive charge configuration incorporating a liner, usually metal, shaped so as to concentrate its explosive force in a particular direction in order to cut or penetrate.
The process of selectively rewarding responses that approximate the desired behavior to an increasingly greater degree. This is one method for teaching a new behavior and can be used as a method of modifying additional behaviors. (See approximation.)
In image and video analysis, a process used to emphasize edge detail in an image by enhancing the high- frequency components.
In image and video analysis, a process used to emphasize edge detail in an image by enhancing the highfrequency components
A tendency to react to stimuli with aggressive behavior.
Elongated crystals form two opposite fans from the same joining point.
Elongated crystals form two opposite fans from the same joining point
A flexible high-explosive charge having mixtures of PETN or RDX and nitrocellulose with rubber polymers and plasticizers. DISCUSSIONThese are also known as Detasheet, Det Sheet, or Flex-X, and are typically less malleable than most Semtex or C-4.
Also known as a two-piece mold, it consists of a top and bottom, each containing a sidewall ring and half of the full-circle tread design.
A widened, flattened area located at various positions on the hair shaft
A small-diameter plastic tube with the interior walls coated with a very thin layer of energetic material (most commonly HMX and aluminum powder) that; when initiated; transmits a detonation.
The outer border or edge of the footwear outsole that defines its overall physical size and shape. Some perimeters may be comprised of a border such as a molded border or a foxing strip.
The size a manufacturer designates for an item of footwear and places on a label in the footwear and/or footwear outsole, and shoe box. There is not a strict dimensional relationship between a manufacturers shoe size and the length and width of the outsole.
The gradual increase or decrease in physical size and content that a manufacturer uses for each half size. In general, each half size will result in an approximate measurement change of 4.2 mm in length of the outsole.
Utilizing a canine to locate target odors in a shoreline environment.
An abnormal connection of low resistance between normal circuit conductors where the resistance is normally much greater; this is an overcurrent situation but it is not an overload.
Multiple copies of an identical (or similar) DNA sequence arranged in direct succession where the repeat sequence unit is 2 base pairs (bp) to 6 bp in length; because STRs generally occur in the DNA outside of the constraints (i.e., selective pressure) of genes, the number of repeat units can vary between individuals;2 variations in STRs may be used for distinguishing individuals, and in biological relationship and ancestry testing
Indicates a recommendation or that which is advised but not required.
Used to indicate that a provision is not mandatory, but recommended as good practice.
The portion of the tire where the sidewall and tread meet.
A variation of the hair form along the shaft, resulting in an irregular and often asymmetrical change of cross-sectional shape.
a variation of the hair form along the shaft, resulting in an irregular and often asymmetrical change of cross-sectional shape.
Added materials (usually metal) which are placed in or around an explosive to intentionally produce additional property damage and injuries. DISCUSSION(1) It should be noted that the term shrapnel is also sometimes colloquially used to denote any pieces from a device that are fragmented by an explosion. (2) Shrapnel can also be included in some military ordnance.
Illumination from a light source at a low angle of incidence, or even parallel, to the surface of the item. Syn. oblique lighting, grazing illumination, raking lighting.
A comparison method performed by placing objects next to one another.
The portion of the tire between the shoulder and the bead that contains the tire information.
a property of fibers referring to the elongation of a fiber in relation to refractive indices.
A property of fibers referring to the elongation of a fiber in relation to refractive indices
To overwrite all available storage areas with a unique sector character sequence.
To overwrite all available storage areas with a unique sector character sequence
An observation that an impression shares a general likeness with a known footwear or tire. (Similar should not be confused with correspond.)
A straight line regression with only one predictor variable (polynomial degree of 1)
The acquisition of images of a single biometric modality from a subject at the same time.Sequential capture over a time scale ( < 1 second) that prevents confounding of bodyparts ( e.g., substituting left iris for right iris) can also be considered simultaneous capturein this context.
DNA sequence variations that occur when a single nucleotide (A, T, C, or G) in the genome sequence is altered; these variations may be used for distinguishing individuals, and in biological relationship and ancestry testing.
Refers to a training exercise in which two subjects walk a straight line and then split into two different directions. When the canine is presented with a scent article from one of the subjects, the canine commences to trail and match the correct person to the scent article. Despite the contamination of scent from the other person on the trail the canine is still able to discriminate between scents and identify the correct subject.
Propellant containing nitrocellulose as the major energetic material
An evaluation of the canine team's ability to complete an exercise where the evaluator knows the outcome and the canine team does not.
An evaluation of the canine team's ability to complete an exercise where the evaluator knows the outcome and the hander does not.
An evaluation of the canine team's ability to complete an exercise where the evaluator knows the outcome and the handler does not.
A dog trained in only one discipline.
An evaluation of the canine team's ability to complete an exercise where the evaluator knows the outcome and the canine team does not.