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.
A grouping or distribution of bloodstains that indicates through regular or repetitive form, order, or arrangement the manner in which the pattern was deposited.
An individual who has completed the prescribed course of study.
An injury to the skin by an object resulting in a pattern that may replicate the design of the object. (Also known as a pattern contusion.)
An estimate of the total drug in the body based on quantitative analysis of blood, urine, and/or tissue samples
Weight for frame and relative proportions of muscle and fat.
Weight for frame and relative proportions of muscle and fat.
The process of evaluating the relative fat composition of the canine. Scores are based on 1 to 5 with normal as a 2-3; or 1-9 with normal as a 4-5.
The process of evaluating the relative fat composition of the canine. Scores are based on 1 to 5 with normal as a 2 to 3; or 1 to 9 with normal as a 4 to 5.
Fluids associated with a human body (e.g., sweat, saliva, blood, vomit, decomposition fluids).
Positive relationship, rapport between canines or a human(s) and a canine.
The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.
A piece of shaped bone or other material, such as plastic or non-stick material, typically used by bookbinders to crease paper and to separate pieces of paper that are stuck together.
Checking to confirm expected outputs are obtained when inputs are at the limits of the software (e.g., testing allele frequencies below the 5/2N minimum threshold or testing upper and lower limits for amplification setup calculations).
ignition component consisting of a cup, explosive mixture, anvil, and covering foil or paper disk that together form the completed primer ready for assembly into the primer pocket of a cartridge case. AFTE Glossary, 6th Ed.
describes the physical phenomenon of X-ray scattering from a crystallo- graphic three-dimensional lattice plane as nl=2dsinq, in which n is any integer, l is the wavelength of the X-ray, d is the crystal plane separation, also known as d-spacing, and q is the angle between the crystal plane and the diffracted beam, also known as the Bragg Angle.
the intertwining of strands in a braiding process to produce a rope structure.
a subclass of aliphatic hydrocarbons with the general formula CnH2n+2, with subordinate chains branching off of the main chain; also known as isoparaffin and isoalkane.
A foot-measuring device.
An organizational structure including policies, procedures, responsibilities and resources necessary for implementing core breath alcohol activities. NOTE The Breath Alcohol Program includes, but may not be limited to, requirements or specifications for reference materials, training of operators, maintenance and calibration of instrumentation, the evidential breath alcohol test sequence, and record retention.
Groups of canines based on canalized or restrictive gene pools derived by selective breeding by humans for behavior or function and / or conformation. When sire and dam come from the same breed, puppies are expected to fall within the broad outlines of the breed standard, which outlines physical and behavioral attributes said to be typical of the breed.
A signal (conditioned reinforcer) that marks (reinforces) a desired behavior. Often called a bridge because it bridges the gap in time from when the animal performs the desired behavior to when it receives the reward. An example would be the use of a clicker.
The quantity of heat required to raise the temperature of one pound of water 1F at the pressure of 1 atmosphere and temperature of 60F; a British thermal unit is equal to 1055 joules, 1.055 kilojoules, and 252.15 calories
An outline within a bloodstain resulting from air in the blood.
A cotton swab or similar collection substrate; used in a relatively non-invasive sample collection technique for scraping the inside of a mouth to collect cells from the inner cheek lining; this is a common method for collecting and preserving samples for DNA testing from known individuals.
An abrupt change in the shape and orientation of a hair shaft with or without a slight twist.
an abrupt change in the shape and orientation of a hair shaft with or without a slight twist.
A training or certification exercise that is conducted on the interior or exterior of a building or structure.
A training or certification exercise that is conducted on the interior of a building or structure.
See Heat Release Rate (HRR)
Form C-216C is a fingerprint form used in Canada to have background record checksperformed. See https://reliabilityscreening.ca/downloads/RCMP_GRC_C216C_Form.pdf[
In computer forensics, a temporary storage area set aside on a processor, in memory, or in a filesystem to keep frequently needed data readily available, designed to speed up processing and improve performance.
Computer systems used to design and manufacture footwear and tires.
A dead human body or the physical remains of a dead human body at one location. Note that this use of the word is different from that often used in law enforcement, which describes the body at a scene where it was found as a corpse, and only as a cadaver once it is under a coroner's or medical examiner's examination.
A fire effect realized in gypsum products, including wallboard, as a result of exposure to heat that drives off free and chemically bound water.
A process where raw rubber passes between a series of large steel rollers. The final roller impresses the outsole design into the rubber that is later cut into soles. Rollers are also used to help prepare raw rubber for the production of rubber biscuits for the compression molding process.
A method of producing adhesive tape by pressing an adhesive to a backing material through a series of heated rollers. The surface appearance depends on the type of roller used.
Characteristic marks left on the backing material due to the manufacturing process.
The set of operations that establish, under specified conditions, the relationship between values indicated by a measuring instrument or measuring system, or values represented by a material, and the corresponding known values of a measurement.
Operation that, under specified conditions, establishes a relation between the quantity value and corresponding indications
The mathematical model that demonstrates the relationship between the concentration of analyte and the corresponding instrument response
A reference material used to determine the concentrations of the analyte elements in the glass matrix. The calibration standard(s) shall have a known elemental composition including a known uncertainty for the reported analytes.
Measurement standard used in calibration
The amount of heat necessary to raise 1 gram of water 1C at the pressure of 1 atmosphere and temperature of 15C; a calorie is 4.184 joules, and there are 252.15 calories in a British thermal unit (Btu).