| Acronym | Definition |
|---|
| NWIS➣National Water Information System |
| NWIS➣North West Interconnected System (Australia) |
| NWIS➣National Water Inventory System (USGS) |
| NWIS➣Nick White Instrumentation Services (est. 2004; Australia) |
| NWIS➣New World International School (Tokyo, Japan) |
| NWIS➣Navy WWMCC Information System |
| NWIS➣Non-Wastewater Irrigated Soils (soil science) |