NX has multiple meanings:
- The "NX" prefix for experimental starships in Star Trek. See NCC (Star Trek).
- A class of Starfleet vessels in Star Trek: Enterprise. See NX class starship.
- NX bit for marking parts of computer memory as "no execute."
- the IATA code for Air Macau
- the NX technology developed by NoMachine that makes remote X11 connections over small bandwidth/high latency links fast enough to work with remote desktops
- In economics, NX is usually used to represent net exports.
- A CAD software product from UGS. See NX (Unigraphics)
- the Nissan Pulsar NX and Nissan NX, a range of subcompact coupes offered by Nissan from the 1980s to 1993.
- Denotes National Express routes; for example NX025 London-Brighton route.