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1. Informal or slang term meaning insane, strange, eccentric or stupid
   - balmy [archaic], barmy, bats, batty, bonkers, buggy [N. Amer], cracked, crackers, daft, fruity, haywire, kooky, kookie, loco, loony, loopy, nuts, nutty, round the bend, around the bend, wacky, whacky, daffy, dippy, nutsy [N. Amer], potty [Brit], daft as a brush [Brit], round the twist [Brit], wacko, cuckoo
    
2. Intensely enthusiastic about or preoccupied with
   "dotty about cars and racing";
   - crazy, wild, gaga

Derived forms: dottier, dottiest

See also: enthusiastic, insane, keen

Encyclopedia: Dotty