GNU
n. uncountablen. Stands for GNU's Not Unix. A large collection of free software that allows people to use and change computer programs without paying or asking for permission.
n. Abbreviation for GNU's Not Unix. An extensive collection of free software, which, when combined with the Linux kernel, forms a complete operating system based on the principles of user freedom and open collaboration.
Many developers prefer using GNU tools for their projects.
The philosophical foundation of the GNU project is rooted in the belief that software users should have the liberty to share, study, and modify the source code they rely upon.
Coined by Richard Stallman in 1983 as a recursive acronym for “GNU's Not Unix”, following convention of naming programs similar to or inspired by existing programs as “(New Name) Is Not (Old Name)”; compare Xinu. Specifically influenced by lack of English words of form ?nu (“?NU is Not Unix”), that gnu is the alphabetically first (and in fact only) English word of the form ?nu (“?’s Not Unix”), that gnu was perceived as a humorous word, and the existence of the song “The Gnu”.
Usually functions as a proper noun referring to the software project or as a modifier for related terms like 'GNU license'.