GRIM, adjective [Latin fremo; Eng. grumble, rumble.] 1. Fierce; ferocious; impressing terror; frightful; horrible; as a grim look; a grim face; grim war. 2. Ugly; ill looking. 3. Sour; crabbed peevish; surly.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI