NNSD
| Acronym | Definition |
|---|---|
| NNSD | Night Night Sweet Dreams |
| NNSD | Nearest Neighbor Spacing Distribution (physics) |
| NNSD | NewAge Net Serial Driver |
| NNSD | No Nonsense Self-Defense (crime prevention) |
| NNSD | Nearest-Neighbor Standard Deviation (spatial dynamics) |
| NNSD | National No Smoking Day (UK and Ireland) |