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.
Surface topography measurement method whereby an optical microscope with illumination of aknown effective wavelength is integrated with an interferometric attachment and producesmultiple successive optical images with interferometric fringes from which the profile or arealsurface topography image is calculated.
PhastGel IEF media are precast homogeneous or gradient polyacrylamide gels containing Pharmalyte as carrier ampholyte.
1 This term is used as an example only, and does not constitute an endorsement of this product by the AAFS Standards Board.
Is a self-contained electrophoresis unit, that consists of a separation-control unit for system control.
1 This term is used as an example only, and does not constitute an endorsement of this product by the AAFS Standards Board.
A method used to obtain digital x-ray images consisting of a photostimulable plate.
A standard two-dimensional image illuminated and captured in the visible wave lengths (380 to 780 nm). This definition is specific to this standard other references may refer to images captured using non-visible wavelengths converted to visible wavelengths as photographic images, but they are not so classified for purposes of this standard. A photographic image is conveyed in a Type-10 record (unless it is an iris image conveyed in Type-17, or a friction ridge image conveyed in one of Types 4, 13, 14, 15, or 19). A non-photographic image is conveyed in a Type-22 record. Original source images are conveyed in Type-20 records and non-biometric associated context images are conveyed in Type-21 records, regardless of the format or source of the image.
Surface topography measurement method in computer vision for measuring the surface normals ofa surface by observing that surface under different lighting conditions. Given sufficient independentlight sources, the surface normals, and thus surface geometry, can be determined for every positionon the surface.
A photosensitive plastic that hardens when exposed to ultraviolet light.
A criterion used to guide the selection of species for comparative analysis and species determination; the selection of species is based on genetic relatedness.
Branch of biology that focuses on the reconstruction of evolutionary history and patterns of relationships among organisms.
A branching diagram that illustrates putative relationships amongst organisms.
NOTE Phylograms are typically generated using genetic sequences and/or morphological characters.
A tree-like branching diagram that depicts the hypothesized evolutionary history among a group of organisms. The tips of the branches represent groups of descendant taxa, whereas the intersections between branches represent common ancestors.
Any external storage material of the voice signal and content information in eitheranalog or digital form. Examples include reel-to-reel recording tape, cassette tape,Compact Disc, and phonograph record.
a hair disorder causing hairs to appear ringed or banded due to the alternating light and dark bands in the hair shaft. The dark bands are a manifestation of abnormal air spaces in the cortex.
See ignition temperature.
Personal Identity Verification.
A fingerprint image resulting from the touching of one or more fingers to a livescanplaten or paper fingerprint card without any rolling motion.
The friction ridge skin on the feet (soles and toes).
Any of a wide range of natural or synthetic organic materials of high molecular weight that can be formed by pressure, heat, extrusion, and other methods into desired shapes.
A permanent distortion of bone’s shape without fracture caused by a force exceeding an element’s elastic limit/elastic modulus/yield point.
Plate or plates used to press the substrate against the prefix, elements, payee perforator, or segments.