| Abbreviation | Definition |
|---|---|
| MULA | Miskatonic University Library Association |
| MULD | Marengo Union Library District |
| MutatRes | Mutation Research (Amsterdam) |
| MVL | MediaWiki Virtual Library |
| MVL | MediaWiki's Virtual Library |
| MVL | My Video Library |
| MVLF | Mill Valley Library Foundation |
| MWDL | Microsoft Wndow Operating Library |
| MWDL | Mountain West Digital Library |
| MWE | Multi-Word Expression |
| MYL | Madge Youtz Library |
| MYLS | Mid York Library System |
| n. | noun |
| n.s. | new series |
| NA | Not Applicable |
| NA | Not Available |
| NAAL | Network Of Alabama Academic Libraries |
| NAC | National Archives of Canada |
| NACL | Networking and Cryptography library |
| NACO | Name Authority Cooperative |