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.
Experiments performed to assess the risk that unintended material may be introduced into a sample from test assay components, instrumentation, the operator, or test procedures.
Existing at or occurring at the same period of time. In Record Type-11, the phrase contemporaneous capture of a voice signal indicates recording of the voice signal atthe time of the speaker vocalization.
Additional related image, audio, or waveform data in support of a biometric record.
the mechanism through which a forensic science practitioner increases or updates knowledge, skills, or abilities (KSAs), reinforces knowledge, or learns of the latest research, developments, or technology related to his or her profession.
A schedule of reinforcement where every occurrence of the behavior is reinforced.
An article or substance that is prohibited by law or regulation within a specific area.
Material of known composition that is analyzed along with unknown sample(s) in order to evaluate the performance of an analytical procedure
A sample used as a quality control measure to demonstrate that the system is working to an optimum level and/or that the integrity of the analytical process is maintained. Material of established origin that is used to evaluate the performance of a test or comparison. A test with an expected positive or negative result often used to confirm the reliability of the method being used.
Samples of known type, run in parallel with experimental, reference, or evidence samples that are used to demonstrate that a procedure is working correctly.
Material of established origin used to evaluate the performance of a test or comparison. Or A test performed to demonstrate that a test method works correctly and to ensure that data are valid. Positive controls confirm that the procedure will produce the expected result. Negative controls confirm that the procedure does not produce an unintended result.
in facial identification, a photographic image captured in accordance with facial identification (FI) or facial recognition (FR) standards or guidelines (for example, a driver's license photo).
A presumed non-coding portion of the mitochondrial DNA molecule analyzed through DNA sequencing, which may be used to determine an individual's mitochondrial haplotype or for taxonomic discrimination. The control region often contains hypervariable regions (in humans: HV1 and HV2) that differ in sequence among non-maternally related individuals. The control region encompasses the D-loop region in humans and other species.
A presumed non-coding portion of the mitochondrial DNA molecule analyzed through DNA sequencing, which may be used to determine an individual's mitochondrial haplotype or for taxonomic discrimination. The control region often contains hypervariable regions (in humans: HV1 and HV2) that differ in sequence among non-maternally related individuals. The control region encompasses the D-loop region in humans and other species.
material of established origin that is used to evaluate the performance of a test or comparison.
Discussion—A control sample should not be confused with a comparison sample. For example, in fire debris, a control sample could include an empty can from the same lot as that used to collect samples.
material of established origin that is used to evaluate the performance of a test or comparison.
Discussion—A control sample should not be confused with a comparison sample. For example, in fire debris, a control sample might include an empty can from the same lot as that used to collect samples.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
An experiment/training/testing exercise in which any defined variable(s) is consistent within specific parameters.
Experiments performed to establish the necessary controls for each procedure, the frequency with which the controls should be performed (e.g., concurrently, daily, before use, etc.) and the performance expectations for each control.
The training of an animal, especially a canine, to obey certain commands while working around a target person in protective gear.
The training of a canine to obey certain commands while working around people.
Heat transfer by circulation within a medium such as a gas or a liquid.
The canine handler's ability to correctly recognize and reward a desired behavior of the canine, or redirect or stop an undesired behavior.
To reproduce information with some level of accuracy.
Discussion—Depending on the process used, copying might result in the loss of data. (Compare bit stream duplicate.)
a twisted or formed structure composed of one or more single or plied filaments, strands, or yarns of organic polymer or inorganic materials.
Discussion—Generally, cords have a diameter less than 3/16 in.
a collective term for twines, cords and ropes made from textile fibers and yarns.
a textile product (yarn, strand, small diameter rope, etc.) placed in the center of a rope and serving as a support for the strands around it.
Discussion—Core can be of any continuous construction including parallel strands, twisted strands or braided strands.
Irregularity or abnormality of the cornea, the clear outermost layer of the eye.
Irregularity or abnormality of the cornea, the clear outermost layer of the eye.
An elected or appointed official whose duty is to oversee medicolegal death investigations, usually for a single county, and ensure certification of cause and manner of death; duties vary based on local enabling statutes.
The application of an aversive stimulus intended to prompt the canine to cease undesired behavior using verbal reprimand, choke collar (slip)/check chain, prong collar, remote trainer, etc.
A training course of action to remediate performance deficiencies with a canine team.
A training course of action to remediate performance deficiencies with a canine team.
A training course of action to remediate performance deficiencies with a canine team.
A training course of action to remediate performance deficiencies with a canine team.
A correlation is an association between two variables, when the variables are related. Correlation does not imply cause.
the main structural component of hair consisting of elongated and fusiform (spindle-shaped) cells; the cortex can contain pigment granules, air spaces called cortical fusi, and structures called ovoid bodies.
the primary anatomical region of a hair between the cuticle region and the medullary region composed of elongated and fusiform cells.
the primary anatomical region of a hair between the cuticle region and the medullary region composed of elongated and fusiform cells.
small air spaces that form between the cortical cells in the hair shaft and, under transmitted light, appear as tiny, dark structures.
small air spaces that form between the cortical cells in the hair shaft and under transmitted light appear as tiny, dark structures.
the relief or definition of the margins of the cortical cells when viewed using transmitted light microscopy.
the relief or definition of the margins of the cortical cells when viewed using transmitted light microscopy.
in knitted fabrics, a row of successive loops in the width direction of the fabric.
The analysis of specimens from subjects within the judicial system or part of an active investigation to determine the presence or absence of drugs or other chemical substances.