| Acronym | Definition |
|---|
| NOS | Network Operating System |
| NOS | Not Otherwise Specified |
| NOS | National Occupational Standards (UK) |
| NOS | National Ocean Science |
| NOS | National Ocean Service (NOAA) |
| NOS | National Ocean Survey (NOAA) |
| NOS | National Open School |
| NOS | National Orthodox School (Amman, Jordan) |
| NOS | NATO Office of Security |
| NOS | Naval Ordnance Station |
| NOS | Nederlandse Omroep Stichting |
| NOS | Net Outside Sales |
| NOS | Network Operations Specialist (Sprint) |
| NOS | Network Optimization Support (Cisco) |
| NOS | Network Optimization System (Sprint) |
| NOS | Never Out of Stock |
| NOS | New Old Stock |
| NOS | New Old Stuff |
| NOS | New Orleans Saints |
| NOS | New Orleans Square (Disneyland) |
| NOS | Next on Stack |
| NOS | Night Observation System |
| NOS | Nitric Oxide Synthase |
| NOS | Nitrous Oxide System |
| NOS | No Organism Seen (medical/microbiology reference) |
| NOS | Non Operational Primitive Sequence |
| NOS | Non-Organic Substance |
| NOS | Northern Tropospheric Oxidants Study |
| NOS | Nosferatu (vampire reference) |
| NOS | Not on Schedule |
| NOS | Not on Shelf |
| NOS | Not One Scratch (condition of items for sale) |
| NOS | Notice of Sale |
| NOS | Novell Operating System |
| NOS | Nuke On Sight |
| NOS | Number Of Sectors |
| NOS | Number of Statements |
| NOS | Netware Operating System |
| NOS | Nitro Oxide System |
| NOS | Non Delay Overclocking System |
| NOS | not of Specific Origin |
| NOS | not Off Set |
| NOS | Notes Object Services |