adj. 25B6; adjective (Brit. informal)
a daft idea : ABSURD, preposterous, ridiculous, ludicrous, farcical, laughable; idiotic, stupid, foolish, silly, inane, fatuous, hare-brained, half-baked; informal crazy, cock-eyed; Brit. informal barmy.
are you daft? : SIMPLE-MINDED, stupid, idiotic, slow, witless, feeble-minded, empty-headed, vacuous, vapid; unhinged, insane, mad; informal thick, dim, dopey, dumb, dim-witted, half-witted, birdbrained, pea-brained, slow on the uptake, soft in the head, brain-dead, not all there, touched, crazy, mental, nuts, batty, bonkers; Brit. informal potty, not the full shilling, barmy, crackers; N. Amer. informal chowderheaded.
she's daft about him : INFATUATED WITH, enamoured of, smitten with, besotted by, very fond of; informal crazy, mad, nuts; Brit. informal potty; informal, dated sweet on.
sensible.