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adj. Archaic
Of, relating to, or induced by a mental disorder.

brain′sick′ly adv.
brain′sick′ness n.


(Psychiatry) relating to or caused by insanity; crazy; mad
ˈbrainˌsickly adv
ˈbrainˌsickness n



insane; crazy; mad.
[before 1000]
brain′sick`ly, adv.
brain′sick`ness, n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.brainsick - affected with madness or insanitybrainsick - affected with madness or insanity; "a man who had gone mad"
insane - afflicted with or characteristic of mental derangement; "was declared insane"; "insane laughter"


Afflicted with or exhibiting irrationality and mental unsoundness:
Informal: bonkers, cracked, daffy, gaga, loony.
Chiefly British: crackers.
Idioms: around the bend, crazy as a loon, mad as a hatter, not all there, nutty as a fruitcake, off one's head, off one's rocker, of unsound mind, out of one's mind, sick in the head, stark raving mad.
References in classic literature ?
He who least regards Such brainsick phantasies lives most at ease.
Nevertheless, although it's utterly brainsick to even imagine that a Sudanese body double could successfully take the place of Buhari, this whole notion of a Buhari imposter in the Presidential Villa resonates because it captures the vast disconnect between the Buhari Nigerians thought they elected in 2015 and the bungling,wimpy, aloof, unjust, and inept Buhari that we have as president now.
But the onslaught of 'the brainsick crew' is fast approaching and 'it is impossible' for the Spanish 'to pass the streets' to d'Avila's lodging (1012) and there deposit the nun.