Acute  —adj. (acuter, acutest) 1 serious, severe (acute hardship). 2 (of senses etc.) Keen, penetrating. 3 shrewd. 4 (of a disease) coming quickly to a crisis. 5 (of an angle) less than 90°. 6 (of a sound) high, shrill. —n. = *acute accent.  acutely adv. [latin acutus pointed]