phenomenonn.

Etymology: < classical Latin phaenomenon (only in plural phaenomena , as the title of a work by Aratus on celestial phenomena, translated by Cicero and others; in post-classical Latin as phenomenon (1620 in a British source)) < ancient Greek ϕαινόμενον , usually in plural τὰ ϕαινόμενα things that appear, appearances, phenomena, celestial phenomena (title of a work by Eudoxus, versified by Aratus), use as noun of neuter of ϕαινόμενος appearing, apparent (to the senses or mind), passive present participle of ϕαίνειν to show, cause to appear (see -phane comb. form). Compare Middle French, French phénomène celestial phenomenon (1557), any of the observed facts which constitute the subject matter of science (1638), fact which impresses one through its novelty or its extraordinary nature (1719), any exterior fact which is perceived through the senses (1737; 1801 in the specific philosophical use), Spanish fenómeno (c1730), Portuguese fenômeno (15th cent.), Italian fenomeno (a1642); compare also German Phänomen (1673).In Phrases after Byzantine Greek σώζειν τὰ ϕαινόμενα. Forms in phœ-, phoe- probably in many cases result ultimately from graphic confusion of the italic forms of œ and æ. Singular phenomenon and plural phenomena are the forms normally preferred in modern use, although singular phenomena and plural phenomenons are both frequently found (especially in speech and in informal writing).