HEAD, SOFT IN THE

(informal) foolish; silly; not in one's right senses. —OEC - Organization and Ethics App Mar 91

(informal) foolish; silly; not in one's right senses. They feel that you're soft in the head or something, and they don't know what to make you out.

(informal) foolish; silly; not in one's right senses. (slang) weak; idle or lazy; foolish.foolish, silly or feebleminded; mentally lacking or deficient in firmness, reality, judgement, etc. Soft means deficient in or lacking hardness. The head is thought of as the seat of understanding, thought or intellect. Thus the phrase soft in the head is used figuratively to describe someone whose intellect, intelligence or mental ability is not firm, solid, etc. Although the origin of this phrase is uncertain, its first recorded use was in 1775.