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 population of individuals based on ancestry or population specificity that reflects a similar genetic, geographic, and environmental background.
assigning an analyte (analytical signal) to one of the set of known individual chemical compounds or to a group/class of compounds.
Discussion—Identification of individual compounds can be required to identify an analyzed sample as one of a definite kind/type/grade/brand of products, material compositions, formulations, etc.
The individual or group responsible for rendering identifications.
The International Electrotechnical Commission.
Improvised Explosive Device
Any liquid or the liquid phase of any material that is capable of fueling a fire, including a flammable liquid, combustible liquid, or any other material that can be liquefied and burned.
any liquid that is capable of fueling a fire.
Discussion—(1) The liquids historically referred to as "flammable liquid" and "combustible liquid" are all considered ignitable liquids. (2) Examples of classes of ignitable liquids include aromatic products, gasoline, isoparaffinic products, naphthenic-paraffinic products, normal alkane products, oxygenated products, and petroleum distillates. Refer to Test Method E1618 for further information about these classes.
Canines specifically trained to locate and respond to the presence of certain classes of ignitable liquids by associated odor. Also known as accelerant detector canine or arson dog.
relatively small amount of ignitable liquid retained in or on a substrate.
Any combustible or flammable liquid.
Ignitible liquid detection canines (IGL canines) are dogs specifically trained to locate and respond to the presence of certain classes of ignitible liquids by associated odor.
The process of initiating self-sustained combustion.
The quantity of heat energy that should be absorbed by a substance to ignite and burn.
a qualitative and destructive test in which a small amount of sample is exposed to a flame or heat.
Discussion—Determining the reactivity of the sample is useful in terms of initial characterization and safe handling.
Minimum temperature a substance should attain in order to ignite under specific test conditions.
The time between the application of an ignition source to a material and the onset of self-sustained combustion.
International Laboratory Accreditation Cooperation.
Substances used non-medically that are prohibited by law, including but not limited to stimulants, cannabis, cocaine, heroin, other opioids, and MDMA.
in computer forensics, to create a bit stream duplicate of the original data.
(1) in image and video analysis, an imitation or representation of a person or thing drawn, painted, or photographed; (2) in computer forensics see bit stream duplicate.
the application of image science and domain expertise to examine and interpret the content of an image, the image itself, or both in legal matters.
in image and video analysis, the process of averaging similar images, such as sequential video frames, to reduce noise in stationary scenes.
in image analysis, the process of comparing images of questioned objects or persons to known objects or persons or images thereof and making an assessment of the correspondence between features in these images for rendering an opinion regarding identification or elimination.
in image analysis, the drawing of conclusions about an image and targets for content analysis include, but are not limited to, the subjects/objects within an image; the conditions under which, or the process by which, the image was captured or created; the physical aspects of the scene (for example, lighting or composition); or the provenance of the image.
in image analysis, the process of retrieving viewable image(s) from a data set.
Any process intended to improve the visual appearance of an image or specific features within an image.
Any process intended to improve the visual appearance of an image or specific features within an image.
In image analysis, a means by which an image is presented for examination or observation.
in image analysis, any activity that transforms an input image into an output image.
in image analysis, a record of the steps used in the processing of an image.
the process by which two images are aligned with each other using a geometric transformation.
See restoration.
in image and video analysis, any process that renders an image, using computer graphics techniques, for illustrative purposes (that is, age progression, facial reconstruction, and accident/crime scene reconstruction).
in image and video analysis, an act of moving images from one location to another.
Thin transparent plastic material that covers the item during an examination using an EDD.
in image and video analysis, any system or method used to capture, store, process, analyze, transmit, or produce an image. Discussion—Such systems include film, electronic sensors, cameras, video devices, scanners, printers, computers, and so forth.
a term that describes a scale pattern in which the scales overlap and the edges have an irregular wavy pattern. This pattern is typical of human hair.
a term that describes a scale pattern in which the scales overlap and the edges have an irregular wavy pattern; this pattern is typical of human hair.
The timing involved in delivering consequences for a response directly following the response in time. This reduces the likelihood of inadvertently reinforcing/punishing some other behavior. (See reinforcement.)
descriptive of substances of the same phase or state of matter that cannot be uniformly mixed or blended.
Make an animal immune to infection, typically by inoculation. (See vaccination.)
To make an animal immune to infection, typically by inoculation. (See vaccination.)
Any of several techniques for obtaining a precipitate between an antibody and its specific antigen by letting both antibody and antigen migrate through the gel from separate wells to form an area of precipitation (also known as ouchterlony double immunodiffusion).
presence of objectivityNote 1 to entry: Objectivity means that conflicts of interest do not exist, or are resolved so as not to adverselyinfluence subsequent activities of the laboratory (3.6).Note 2 to entry: Other terms that are useful in conveying the element of impartiality include freedom fromconflict of interests, freedom from bias, lack of prejudice, neutrality, fairness, open-mindedness, even-handedness, detachment, balance.[SOURCE: ISO/IEC 170211:2015, 3.2, modified The words the certification body have been replacedby the laboratory in Note 1 to entry, and the word independence has been deleted from the list inNote 2 to entry.]
presence of objectivityNOTE 1 Objectivity means that conflicts of interest do not exist or are resolved so as not to adversely influencesubsequent activities of the inspection body.NOTE 2 Other terms that are useful in conveying the element of impartiality are: independence, freedom from conflictof interests, freedom from bias, lack of prejudice, neutrality, fairness, open-mindedness, even-handedness, detachment,balance.
Presence of objectivity