Nai
- Airline codes-N
- County of Nairn
- McAfee
- NAL (disambiguation)
- NASA Astrobiology Institute
- Nai (album)
- Nai (caste)
- Nai (noble title)
- Nai (pan flute)
- Nai (song)
- Nai language
- Nai, Rajasthan
- Nai, Razavi Khorasan
- Nairobi
- National Academy of Inventors
- National Amusements
- National Archives of India
- National Association for Interpretation
- Natural Alternatives International
- Nay (disambiguation)
- Netherlands Architecture Institute
- Network Access Identifier
- Network Advertising Initiative
- New Alchemy Institute
- New Atlantic Initiative
- Ney (disambiguation)
- North Allegheny Intermediate High School
- Norwegian Air International
- Scintillator
- Sodium iodide