[phe.nom.e.non] n, pl -na or -nons [LL phaenomenon, fr. Gk phainomenon, fr. neut. of phainomenos, prp. of phainesthai to appear, middle voice of phainein to show--more at fancy] (1605) 1 pl phenomena: an observable fact or event
2. pl phenomena a: an object or aspect known through the senses rather than by thought or intuition b: a temporal or spatiotemporal object of sensory experience as distinguished from a noumenon c: a fact or event of scientific interest susceptible of scientific description and explanation 3 a: a rare or significant fact or event b pl phenomenons: an exceptional, unusual, or abnormal person, thing, or occurrence usage see phenomena