Siw
Siw stands for:
- the second month according to the religious Jewish calendar, see Ijjar
SIW is an abbreviation for:
- Shipping and Inselbahn Wangerooge, see Wangerooger Inselbahn
- Socialist International Women
- Substrate Integrated Waveguide , a high frequency line
SiW stands for:
- Pointless in space , fan club and parody of the spaceship Enterprise
