SIV
- Block cipher mode of operation
- Federal Executive Council (Yugoslavia)
- S IV
- SIW (disambiguation)
- Sheffield International Venues
- Silicon-vacancy center in diamond
- Simian immunodeficiency virus
- Siv (given name)
- Siv Kladenets
- Siv, Iran
- Siva (disambiguation)
- Special Immigrant Visa
- St Ives railway station
- Steve (disambiguation)
- Stress migration
- Structured investment vehicle
- Sullivan County Airport
- Surinaamse Islamitische Vereniging
- Swine influenza
- Sydney Intervarsity Choral Festival