Meaning

adjective of an angle; between 90 and 180 degrees

adjective (of a leaf shape) rounded at the apex

adjective lacking in insight or discernment; ; - Jasper Griffin

originFrom Middle English obtuse, from Latin obtūsus (“blunt, dull; obtuse”), past participle of obtundere, from obtundō (“to batter, beat, strike; to blunt, dull”), from ob- (“against”) (see ob-) + tundō (“to beat, strike; to bruise, crush, pound”) (ultimately from Proto-Indo-European *(s)tewd-, from *(s)tew- (“to hit; to push”)). More at obtund.

Etymology from Wiktionary, CC BY-SA 3.0