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 composition of DNA fragments that represents common alleles at a locus
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.
A 10-print search is conducted on a fingerprint record which is often a reproduction of all ten fingers. An automated 10-print inquiry normally requires a minutiae search of only the thumbs or index fingers. Submitted fingerprints commonly have sufficient clarity and detail to make searching of more than two fingers unnecessary. This can be performed by a computer, in a 'lights out' setting if the quality of the record is high enough. A latent print search can be utilized for searching unknown deceased records when multiple fingers are not printable or present, and/or the quality of the recording is poor. A latent print search can often be more time consuming and require additional expertise. A latent print examiner conducts an analysis of the quality and quantity of information in the print and marks the individual minutiae in the print according to each individual AFIS system's requirements. Due to the lower quality and quantity of information often found with PM fingerprints, the analysis of each impression by a latent print examiner along with the marking of the specific minutiae for AFIS searches can yield better results. The AFIS system typically returns a candidate list of possible individuals that must be manually compared by the latent print examiner to determine if there is an identification.
A container format used for multimedia applications. It was developed by the ThirdGeneration Partnership Project 2(3GPP2) and is similar to 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 companding algorithm used outside of North America and Japan that optimizes ananalog telephone band signal while digitizing.
Analog-to-digital
The American Association of Blood Banks.
The American Association of Motor Vehicle Administrators.
The American Board of Forensic Odontology
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.
The American Board of Orthodontics
Wearing away rubber from tires by friction due to high speed, locked wheel braking. Abrasion will be at right angles to the direction of travel, also on shoulder and sidewall.
any substance exhibiting the property of absorption. Hawley's6
the stationary phase for adsorption TLC.
the penetration of one substance into the inner structure of another, as distinguished from adsorption, in which one substance is attracted to and held on the surface of another. Hawley’s5
a fuel or oxidizer, often an ignitable liquid, intentionally used to initiate a fire or increase the rate of growth or spread of fire. NFPA 921, 3.3.2
DISCUSSION—(1) Whether a substance is an accelerant depends not on its chemical structure but on its use. (2) This term is not used in fire debris analysis but is included in this standard for historical purposes and for clarity of meaning when used by stakeholders.
A fuel or oxidizer, often an ignitible liquid, intentionally used to initiate a fire or increase the rate of growth or spread of fire.
voltage/electrical potential applied to the filament that accelerates the electrons emitted by the electron gun/filament.
Flegler
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.
See randomly acquired characteristic.A feature on a footwear outsole or tire tread resulting from interaction with an object(s) including, but not limited to: cuts, scratches, tears, holes, stone holds, abrasions and the acquisition of debris. The position, orientation, size and shape of these characteristics differentiate a footwear outsole or tire tread from other footwear outsoles or tire tread with similar class characteristics. Randomly acquired characteristics are essential for an identification of a particular item of footwear or tire as the source of an impression.
A small blood drop produced as a by-product of drop formation.
The formal recognition by an independent accreditation body that a medicolegal system, office, or agency meets or exceeds a prescribed set of standards.
Third party evaluation of a forensic science service provider based on a particular standard(s), other relevant documents and attestation of competence to carry out specific tasks.
An organization responsible for management and implementation of the system to set standards or guidelines within the relevant field.
An independent body that verifies that a medicolegal system, office, or agency meets nationally or internationally recognized quality standards established through consensus, and is competent to carry out specific conformity assessment tasks to perform accreditation.
An authoritative body that performs accreditation. The authority of an accreditation/accrediting body is generally derived from government, national, or international standards.
The designation given to those who are able to demonstrate they meet or exceed the standards or guidelines set by the appropriate accreditation body
An organization that performs examinations and/or inspections of materials, products, installations, plants, processes, work procedures or services, where examination activities are evaluative and not considered testing, and that has received formal recognition by an accrediting body that it meets or exceeds a list of standards to perform specific inspections/examinations.
The closeness of agreement between a test result and the accepted reference value. 1) In practice, the accepted reference value is substituted for the true value. 2) The term "accuracy," when applied to a set of test or measurement results, involves a combination of random components and a common systematic error or bias component. 3) Accuracy refers to a combination of trueness and precision.
The degree of conformity of a measured quantity to its actual (true) value.
Closeness of agreement between a measured quantity value and a true quantity value of a measurement
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
The measure of imaging system's practical limit to distinguish between separate adjacent elements, typically by imaging a known reference standard.
The measure of imaging system's practical limit to distinguish between separate adjacent elements, typically by imaging a known reference standard.
Pressure waves in a media that have information content.
In computer forensics, the process of using an access interface to read digital data from a digital source and to create a destination object.
a form of carbon characterized by high adsorptivity for many gases, vapors, and colloidal solids that is typically activated by heating to 800–900°C with steam or carbon dioxide, which results in a porous internal structure; also known as activated charcoal.
homogenous mixture of activated charcoal and an inert polymer formed into a strip; a convenient adsorption medium
a homogenous mixture of activated charcoal and an inert polymer formed into a strip; a convenient adsorption medium for fire debris analysis.
heating of the adsorbent layer on a plate to dry out the moisture and maximize its adsorptive power.
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).