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.
The presence of more than one mitochondrial DNA (mtDNA) sequence or type within a single individual.
In computer forensics, a sector in the current configuration of a drive that cannot be accessed by read and write commands without changing the drive con- figuration. DISCUSSIONSectors in a host protected area would be hidden data sectors.
In computer forensics, a sector in the current configuration of a drive that cannot be accessed by read and write commands without changing the drive configuration
A material that is capable of sustaining a reaction front that moves through the unreacted material at a speed equal to or greater than that of sound in that medium [typically 1000 m/sec (3000 ft/sec)]; a material capable of sustaining a detonation. (See also detonation.)
Energetic materials that support a supersonic detonation wave, irrespective of the ambient condition of confinement; sometimes abbreviated HE.
Descriptive of an explosive that undergoes complete reaction (or detonation) of the material as designed.
In this document, it refers to a MS instrument that can give at least 10,000 nominal mass resolving power at full width of the peak at half its maximum height (FWHM) for the compound of interest.
A rapid pressure rise or high-force explosion characterized by a shattering effect on the confining structure or container and long missile distances.
An abnormal formation of the hip socket.
A graph of a frequency distribution in which rectangles with bases on the horizontal axis are given widths equal to the class intervals and heights equal to the corre- sponding frequencies. DISCUSSIONIn digital images, a histogram is frequently used to document the number of pixels of a given brightness value (for example, 0-255).
A graph of a frequency distribution in which rectangles with bases on the horizontal axis are given widths equal to the class intervals and heights equal to the corresponding frequencies
A calibration that was performed and stored prior to the preparation and/or analysis of the case samples and quality control samples
Homemade Explosives.
A 'dummy' device designed to appear as a bomb; but missing explosive or other components such that the device would not function as a bomb.
The result of erosion of a footwear outsole or tire tread that is so extreme that it results in removal of the outer layers of the outsole or tread materials, often resulting in irregular edges. These irregular edges are randomly acquired characteristics. Random holes due to punctures are also randomly acquired characteristics.
In facial identification, a process of comparing faces by looking at the face as a whole and not the component parts in isolation.
In facial identification, a process of comparing faces by looking at the face as a whole and not the component parts in isolation
Often abbreviated as HME; any explosive not commercially manufactured; also known as improvised explosives.
a series of organic compounds in which each successive member has one more repeating unit (for example, methylene group, CH2) in its molecule than the nearest preceding member.
A segment of DNA consisting of repeats of a single nucleotide; may cause slippage during amplification and sequencing.
Cross-sectional shape of the contact between horizons.
In facial identification, a bright area of light reflecting on a face that reduces the visibility of features.
In facial identification, a bright area of light reflecting on a face that reduces the visibility of features
hue is that attribute of a color in the Munsell color system by which we distinguish red from green, blue from yellow, etc
Non-target person placed within a search area.
Non-target person placed within a search area.
Non-target person placed within a search area.
Non-target person placed within a search area.
The analysis of specimens for driving while impaired cases, drug-facilitated crimes, and other impairment cases (e.g., child custody).
The way in which human scent moves or reacts in a given environment. Factors that influence the dispersion of scent may include wind, temperature, air currents, and topography. An example would be a plume of scent that a canine has been trained to follow to its target.
A particular person's scent collected for use for investigative purposes.
A particular persons scented article collected for use for investigative purposes.
A particular persons scented article collected for use for investigative purposes.
A particular persons scented article collected for use for investigative purposes.
A canine trained to locate and indicate items in question by means of detecting human scent.
Individual that laid a track/trail for a canine to follow to the exclusion of all other trails
Individual that laid a track/trail for a canine to follow to the exclusion of all other trails.
Individual that laid a track/trail for a canine to follow to the exclusion of all other trails.
Search determinedly for someone or something
Search determinedly for someone or something.
The innate impulse of a canine to search determinedly using the senses of smell, sight, hearing, and/or taste.
The science of providing for the needs of an animal including housing, daily care, feeding, exercise, and meeting the behavioral/mental/emotional needs of the animal.
The science of providing for the needs of an animal including housing, daily care, feeding, exercise, and meeting the behavioral/mental/emotional needs of the animal.
An explosible heterogeneous mixture, comprising gas with suspended solid or liquid particulates, in which the total flammable gas concentration is 10 percent of the lower flammable limit (LFL) and the total suspended particulate concentration is 10 percent of the minimum explosible concentration (MEC). [68, 2018]
Spontaneously self-igniting upon mixing of components or when one component contacts another component; examples include the reaction of potassium permanganate with glycerin; and the reaction of calcium hypochlorite with polyethylene glycol.
Any substance that will spontaneously ignite or explode upon exposure to an oxidizer.
A segment of DNA that often contains polymorphisms and thus is useful for differentiating taxa or unrelated individuals.
A section of the human mtDNA control region spanning nucleotide positions 16024-16365, that often differs among non-maternally related individuals.
A section of the human mtDNA control region spanning nucleotide positions 16024-16365, that often differs among non-maternally related individuals.
A section of the human mtDNA control region spanning nucleotide positions 73-340, that often differs among non-maternally related individuals.