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 The Organization of Scientific Area Committees for Forensic Science
    
      
  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.



Keyword Search
  
  
  Searches term, definition, and source for any of these keywords.
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  Searches term name.
  OSAC Committee
  
  
  - Any -Bloodstain Pattern AnalysisCrime Scene Investigation & ReconstructionDigital EvidenceDogs & SensorsFacial and Iris IdentificationFire & Explosion InvestigationFirearms & ToolmarksFootwear & TireForensic AnthropologyForensic Document ExaminationForensic NursingForensic OdontologyForensic ToxicologyFriction RidgeFSSBHuman Forensic BiologyIgnitable Liquids, Explosives & Gunshot ResidueInterdisciplinaryMedicolegal Death InvestigationSeized DrugsSpeaker RecognitionTrace MaterialsVideo/Imaging Technology & AnalysisWildlife Forensic Biology
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Displaying 1 - 5 of 5
      Export results (CSV)X-Ray Diffraction (Xrd)
  The diffraction of a beam of X-rays, usually by the three-dimensional periodic array of atoms in a crystal that has periodic repeat distances (lattice dimensions) of the same order of magnitude as the wavelength of the X-rays (1).
            
            Committee
                    Trace Materials

            Date Added to Lexicon
                                06/12/2023

            **Standard Source** (Designation Number Title of Standard. Publisher, Place, Year.)
          ANSI/ASTM E3294-22 Standard Guide for Forensic Analysis of Geological Materials by Powder X-Ray Diffraction. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2022.
                          Source link
                  *Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org*
      Term link
  X-Ray Diffraction Pattern Or Diffractogram
  The characteristic interference pattern obtained when X-rays are diffracted by a crystalline substance; the geometry of the pattern is a function of the repeat distances (lattice dimensions) of the periodic array of atoms in the crystals; the intensities of the diffracted beams give information about the atomic arrangement, and unit-cell dimensions (adapted from Neuendorf et al., Glossary of Geology 2005).
            
            Committee
                    Trace Materials

            Date Added to Lexicon
                                06/12/2023

            **Standard Source** (Designation Number Title of Standard. Publisher, Place, Year.)
          ANSI/ASTM E3294-22 Standard Guide for Forensic Analysis of Geological Materials by Powder X-Ray Diffraction. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2022.
                          Source link
                  *Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org*
      Term link
  X-Ray Powder Diffraction
  Diffraction of a beam of X-rays by planes of atoms in a powdered crystalline sample; the powders are prepared so they ideally represent all possible crystal orientations to the X-ray beam (adapted from Ref (1)).
            
            Committee
                    Trace Materials

            Date Added to Lexicon
                                06/12/2023

            **Standard Source** (Designation Number Title of Standard. Publisher, Place, Year.)
          ANSI/ASTM E3294-22 Standard Guide for Forensic Analysis of Geological Materials by Powder X-Ray Diffraction. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2022.
                          Source link
                  *Reprinted, with permission, from ASTM, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, https://www.astm.org*
      Term link
  Xml
  Extensible Markup Language. A convention for marking up and tagging data forelectronic transmission. An XML package is built from text content marked up with texttags such as . In XML one can create as many tags as needed.These tags describe the type of content they contain rather than formatting or layoutinformation. The types of tags allowed in an XML file are typically defined andconstrained by a specification such as an XML Schema Definition (XSD).
            
            Committee
                    Interdisciplinary

            Date Added to Lexicon
                                06/12/2023

            **Standard Source** (Designation Number Title of Standard. Publisher, Place, Year.)
          ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011.
                          Source link
      Term link
  Xml 3D Surface Profile X3P
  X3P is an open file format for the exchange of three dimensional surface topography data instandard units. Details are specified in ISO 25178-72.
            
            Committee
                    Firearms & Toolmarks

            Date Added to Lexicon
                                06/12/2023

            **Standard Source** (Designation Number Title of Standard. Publisher, Place, Year.)
          ANSI/ASB 062 Standard for Topography Comparison Software for Toolmark Analysis. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021.
                          Source link
      Term link
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