adjective, beast·li·er, beast·li·est.
- of or like a beast; bestial.
- Informal. nasty; unpleasant; disagreeable.
adverb
- Chiefly British Informal. very; exceedingly: It’s beastly cold out.
- British Informal. disagreeably; outrageously: beastly rude.
adjective -lier or -liest
- informal unpleasant; disagreeable; nastybeastly weather
- obsolete of or like a beast; bestial
adverb
- informal (intensifier)the weather is so beastly hot
c.1200, “brutish, sensual, debased;” late 14c., “in the manner of a beast,” from beast + -ly (1). Weakened in British upper crust use to “awfully, exceedingly” by mid-19c. Beastly drunk is from 1803.