The term Wildebeest is a large, antelope-like mammal native to Africa. The two crossword solutions for this term are GNU (3 letters) and GNUS (4 letters). GNU is an acronym for 'GNU's Not Unix, ' which is a free, open source operating system developed in the 1980s. GNUS is a newsreader program used to access Usenet newsgroups. Both GNU and GNUS are related to the term Wildebeest as they are both computer programs that are related to the African mammal.