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.
Training
Training Aid
Target odor/scent sources used for training.
Training Aid
Target odor/scent sources used for training.
Training Log Training Record
A record used to document the training of a canine, canine handler or canine team, maintained separately from other records, i.e., assessments, certifications or discipline-related deployment records. A record documenting the performance of the canine team, especially an account of an act or occurrence kept in writing or some other permanent form, i.e. electronic format which is discoverable.
Training Program
A written description of activities to be performed for the purpose of establishing and maintaining competency and job-related knowledge, skills or abilities
Transaction
A group of records with information and biometric data concerning a particularindividual that is transmitted and / or stored as a complete unit.
Transaction Element
A record type / field / subfield / information item / value.
Transcode
Transcoding
Any transfer, compression, manipulation, re-formatting or re-storage of the originaldata. Transcoding can be lossless or lossy.
Transfer Impression
Transfer Stain
Transillumination
Imaging technique with light transmitted through an excised specimen.
Transition
A mutation that results in a change from one purine to the other purine (e.g., A-to-G) or one pyrimidine to the other pyrimidine (e.g., C-to-T).
transition
A mutation that results in a change from one purine to the other purine (e.g., A to G) or one pyrimidine to the other pyrimidine (e.g., C to T).
transitory defect
An anomaly such as dust, hair, dirt, or fiber that attaches itself to the material of the stamp die and can create a non-print area in the impression. A transitory defect is not part of the die or stamp; therefore, it can easily be removed by use or cleaning.
transmitted light
Illumination that passes through a document.
Transport Container
A container used to appropriately move training aids in compliance with storage and handling guidelines of the Federal, state, and/or local agencies' policy.
Transversion
A mutation that results in a change from a purine to pyrimidine or vice versa (e.g., A-to-T).
transversion
A mutation that results in a change from a purine to pyrimidine or vice versa (e.g., A to T).
trauma description
Reporting of the location, dimension(s), and other observed characteristics of the skeletal defect(s).
trauma interpretation
Explanation regarding the mechanism, timing, direction of impact(s), and/or minimum number of impacts associated with skeletal defect(s) using quantitative and/or qualitative evidence.
trauma mechanism
The external factors that produce a skeletal defect.
Tread
Tread Block
Tread Depth
Tread Depth Gauge
Tread Design
Tread Design
A term used to describe a specific pattern or arrangement of design elements on a tire treadtypically associated with a manufacturer and having a name and/or style number (also used todescribe footwear outsoles).
Tread Wear Indicator
Tread Wear Indicator
Bands of raised rubber, sometimes called wear bars, that are 2/32 of an inch above the bottom of the main grooves of a tire.
Tread Width
Treadprint
Tri-linear Array
Trichonodosis
Trichoptilosis
Trichorrhexis Invaginata
Trichorrhexis Nodosa
Trichoschisis
Trigger Pull
The amount of force which must be applied to the trigger of a firearm to cause sear release. The direction of the applied force is approximately parallel to the bore axis.b
Trigger Pull
The amount of force which must be applied to the trigger of a firearm to cause sear release.
Triglyceride
Triple Base
Triple-Base
Turn
A conversation is a sequence of conversational turns. A turn is when an individualspeaks for a continuous period of time. Individual turns from different people mayoverlap when they speak simultaneously. However, typically a turn is referred to in aquestion / response environment.
Turning Diameter
Twist
Two-Dimensional Impression
type A evaluation (of uncertainty)
Method of evaluation of uncertainty by the statistical analysis of series of observations (e.g., relative standard deviation of a historical data set of control results)
type B evaluation (of uncertainty)
Method of evaluation of uncertainty by means other than the statistical analysis of series of observations (e.g., obtaining the uncertainty associated with a CRM from its certificate of analysis)
Type I Error
This is the mistake when one rejects the null hypothesis (one states that there is an effect) and it is true (there is really NO effect). This is also called a false positivedetecting an effect where none exist. (see false positive.)