Etymology: < classical Latin acūtus sharpened, pointed, sharp, tapering, having sharp needles, keen, discriminating, keen-witted, shrewd, nimble, quick, pungent, acrid, high-pitched, piercing, shrill, treble, (of angles) less than a right angle, (of accent) acute, (of a syllable) having an acute accent, (of diseases) violent, use as adjective of the past participle of acuere to sharpen, to make keener, to incite, to intensify, to accent (a syllable in a word) < acus needle (see acicula n.). With use as noun compare post-classical Latin acutus acute accent (from 4th cent. in grammarians), use as noun (short for accentus acutus) of the masculine of classical Latin acūtus, and also post-classical Latin acuta acute fever, ague (13th cent. in British sources; also in continental sources), use as noun of the feminine of classical Latin acūtus. Compare Anglo-Norman and Old French, Middle French acu, Middle French acut (13th cent.; a reborrowing from Latin, beside the regularly developed form aigu).The use in classical Latin with reference to accent is after corresponding use of ancient Greek ὀξύς sharp, acute (see oxy- comb. form¹). With acute accent n. at Compounds 2 compare the following early use of Latin acutus accentus in an English context:OE Byrhtferð Enchiridion (Ashm.) (1995) iii. iii. 174 Oxia ys acutus accentus, þæt ys gescyrpt accent.

Etymology: Probably partly < acute adj., and partly < classical Latin acūtus, past participle of acuere (see acute adj.). Compare post-classical Latin acutare to sharpen (4th cent.), to lengthen, accent (9th cent., 13th cent. in British sources).