SIWC
| Acronym | Definition |
|---|---|
| SIWC | Sydney International Wine Competition |
| SIWC | Sexual Intercourse without Consent (Montana) |
| SIWC | Soroptimist International of Washoe County (Reno, NV) |
| SIWC | Sanibel Island Writers Conference |
| SIWC | Shanghai International Wine Challenge (wine competition; Shanghai International Wine and Spirits Fair; Shanghai, China) |
| SIWC | Seaborne Information Warfare Course |