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.
(Allelic) Ladder
A composition of DNA fragments that represents common alleles at a locus
(Xml) Schema
An XML schema declares the XML elements, their structure and order. A schemaassigns data types, names, and attributes to the elements. A schema may be used tovalidate the structure and content of an XML package.
3G2
A container format used for multimedia applications. It was developed by the ThirdGeneration Partnership Project 2(3GPP2) and is similar to 3GP.
3Gp
A container format used for multimedia applications. It was developed by the ThirdGeneration Partnership Project (3GPP). It is used on 3G mobile phones, and some 2Gand 4G phones.
A-Law
A companding algorithm used outside of North America and Japan that optimizes ananalog telephone band signal while digitizing.
A/D
Analog-to-digital
AABB
The American Association of Blood Banks.
AAMVA
The American Association of Motor Vehicle Administrators.
ABFO
The American Board of Forensic Odontology
ABFO # 2 Reference Scale
A right angle ruler designed by the ABFO that is used for patterned injury imagery. It includes three circles that are useful to determine distortion due to photography atdifferent angles. The ruler itself is manufactered by several different sources. The correct name is the ABFO #2 Reference Scale, but it is commonly known as the ABFO# 2 ruler.
ABO
The American Board of Orthodontics
Abrasion
absent character
A character or character combination which is present in one body of writing but is not present (for example, does not have a corresponding character) in another body of writing. (SWGDOC E01)
Absorbent
Absorption
Accelerant
Accelerant
A fuel or oxidizer, often an ignitible liquid, intentionally used to initiate a fire or increase the rate of growth or spread of fire.
Accelerating voltage
Accident
An unplanned event that interrupts an activity and sometimes causes injury or damage or a chance occurrence arising from unknown causes; an unexpected happening due to carelessness, ignorance, and the like.
accident (manner of death)
Unexpected or not reasonably foreseen death that results from an injury or toxicity.
accidental characteristic
One that falls outside of the writer's range of variation, and that would not be expected to be repeated in the writing because it may be an anomaly.
Accompanying Drop
accreditation
Formal recognition by an independent accreditation body that a medicolegal system, office, or agency meets or exceeds a prescribed set of standards.
Accreditation Body
An organization responsible for management and implementation of the system to set standards or guidelines within the relevant field.
Accreditation/Accrediting Body
An authoritative body that performs accreditation. The authority of an accreditation/accrediting body is generally derived from government, national, or international standards.
Accredited
The designation given to those who are able to demonstrate they meet or exceed the standards or guidelines set by the appropriate accreditation body
Accredited Inspection Body
Accuracy
accuracy
The degree to which the result of a measurement, calculation, or specification conforms to the correct value or a standard.
Accuracy
The degree of conformity of a measured quantity to its actual (true) value.
accuracy
closeness of agreement between a measured quantity value and a true quantity value of a measurement
Accuracy Studies
Studies performed to assess the degree of conformity of a measured quantity to its actual (true) value. In probabilistic genotyping, these are studies performed to establish that the calculations made by the probabilistic genotyping system are correctly executed, and that the results obtained produce the expected likelihood ratio for situations where the calculations can be performed manually or with an alternate software program or application. Such situations include profile results from single source samples, 2-person mixtures with unambiguous major and minor contributors, and 2-person mixtures with equal mixture proportions. However, profile results where the ground truth is not known are not suitable for accuracy studies
Achievable Resolution, Resolving Power
Acoustic Signal
Pressure waves in a media that have information content.
Acquisition
Activated carbon
Activated Carbon Strip (ACS)
Activation energy
Active Alert
A type of response that the canine displays/indicates in a manner that may disturb the environment and or forensic evidence (i.e., dig, bark, scratch, paw, jump, and bite after the detector canine has detected a trained odor/scent).
active coat
A coating layer which contains the primary image (color) forming components.
Active Fire Protection System
A system that uses moving mechanical or electrical parts to achieve a fire protection goal.
Activity Drive
The subconscious impulse to be constantly physically active.
activity level
in comparative examinations, the factors by which the material was left (transfer) and remained (persistence).
Discussion—Factors include the presence of the evidence in a particular location (for example, glass found embedded in the sole of a shoe versus glass found on a shirt), quantity (for example, multiple glass fragments versus a single glass fragment), and condition (for example, pulled hair versus shed hair).
Discussion—Alternative hypotheses of alleged activities may also be part of the factors considered.
Ad hoc image
ADA
The American Dental Association
Additive (Modifier)
Additives
Adhesive
Adhesive Lifter
Adipocere
Semi-solid/liquid (cheesy) decomposition product of human remains.