слабоумный

1) General subject: Feebleminded, anile, batchy, cousin Betty (человек), cretinous, daft (о человеке), deficient, demented, doddering, feeble minded, feeble-minded, foolish, gaga, half wit, half-wit, halfwitted, idiot, imbecile, mentally deficient, moron, moronic, sackless, silly, slow witted, slow-witted, soft, soft (weak) in the head, subnormal, weak minded, weak-headed, weak-minded, witless

2) Medicine: ament, defective, half-witted, irrational, mentally defective, retarded

3) Colloquial: caky, daft, numpty

4) Slang: meat-head

5) American: retard, retardee

6) Obsolete: changeling

7) Rare: doddery, fool

8) Law: person of weak mind

9) Australian slang: loony, loopy

10) Psychology: incomplete

11) Jargon: balmy, half-baked, gomer ("Stop acting like a gomer!")

12) Business: mentally handicapped, mentally retarded

13) leg.N.P. lunatic

14) Aviation medicine: mental defective, mental(ly) defective

15) Makarov: soft in the head, weak in the head

16) Archaic: fatuous