si

Short definition from Wiktionary

Noun

1. 1
   A syllable used in solfège to represent the seventh note of a major scale.
2. 2
   Initialism of signal integrity.
3. 3
   Initialism of systems integration.
4. 4
   Initialism of self-injury.
5. 5
   Initialism of suicidal ideation.
6. 6
   Initialism of self-insertion (of the author into fan fiction).
7. 7
   Initialism of spark ignition.
8. 8
   Initialism of supporting information.
9. 9
   Initialism of special intelligence.
10. 10
    Initialism of systematic internaliser.
11. 11
    Initialism of swarm intelligence.
12. 12
    Initialism of synthetic intelligence.
13. 13
    Initialism of sales invoice.
14. 14
    Initialism of statutory instrument.
15. 15
    Initialism of subinspector (of police, etc).
16. 16
    Initialism of surface interval.

Proper noun

1. 1
   International System of Units
2. 2
   Initialism of Smithsonian Institution.
3. 3
   Initialism of Sports Illustrated.
4. 4
   A diminutive of the male given name Simon.
5. 5
   A diminutive of the male given name Silas.
6. 6
   A river in Shandong, China.
7. 7
   A county of Suzhou, Anhui, China.
8. 8
   Various prefectures of imperial China.
9. 9
   Alternative form of Xi.

Adjective

1. 1
   Initialism of sacroiliac.

Symbol

1. 1
   Chemical symbol for silicon.