Definition of "SD"

SD

proper noun
1. Initialism of South Dakota.
2. (uncountable) Initialism of Secure Digital: a non-volatile memory card format developed for use in portable devices.
noun
plural SDs
1. Initialism of school district.
2. (law enforcement) Initialism of sheriff's department.
3. (mathematics) Initialism of standard deviation.
4. (video games) Initialism of self-destruct.
5. (genetics) Initialism of segmental duplication.
  Quotations
  We estimated that the following percentage of elements were correctly assembled: 95.4% of alpha satellites; 91.5% of human satellites 2 and 3; 97.7% of segmental duplications (SDs); 94.3% of variable number tandem repeats (VNTRs); 94.2% of short tandem repeats (STRs); and 98.8% of all human repeats26.
  2023 May 11, Wen-Wei LiaoMobin AsriJana Ebleret al., “A draft human pangenome reference”, in Nature, volume 617, page 313
noun
uncountable
1. (television) Initialism of standard definition (“typically 640×480 pixels”).