An Etymological Dictionary of Astronomy and Astrophysics

A prefix meaning “not.”

Etymology (EN): From O.Fr. non-, from L. non “not,” from Old L. noenum “not one;” in some cases perhaps from M.E. non “not” (adj.), from O.E. nan.

Etymology (PE): Nâ- “no, not,” variants na, ni, ma- (prohibitive) “not;” from
Mid.Pers. nê, ma “no, not;” O.Pers. naiy, nai “not;” Av. nôit, naē “not;” cf. Skt. ná “not;” cf. L. ne-, in-, un-; Gk. ni; Lith. nè; O.C.S. ne “not;” PIE *ne-.