| beef-witted | beef-brained, thick-headed, brainless |
| bleak | pale, pallid, sickly |
| boiled-brain | hothead, maniac, headstrong fellow |
| brain | understand, comprehend, grasp |
| brain | murder, dash the brains out of |
| brain | (plural) witticisms, clever remarks |
| brained | furnished with a brain, addle-brained |
| brainsick, brain-sick | foolish, addle-headed |
| brainsick, brain-sick | mad, foolish, frantic |
| brain-sickly | foolishly, in such an addle-headed way |
| fume | harmful vapour [rising from the stomach to the brain] |
| globe | head, brain |
| green-sickness | sexual squeamishness, sickly naivety |
| headpiece | brain, intellect |
| madcap | mad-brained fellow, lunatic |
| pia mater | [Latin] dutiful mother: membrane covering the brain; brain |
| prain | Welsh pronunciation of 'brain' |
| sick | pale, wan, of a sickly hue |
| sickly | cover with a sickly hue, make pallid |
| sickly | weak, feeble, dying |
| sickly | of sickness, invalid |
| skipper | light-brain, frivolous wretch |
| sodden-witted | stew-brained, limp-minded, alcohol-crazed |
| tickle-brain | type of strong drink |
| understand | use their brains |
| understanding | intellect, intelligence, brain |
| ventricle | cavity within the brain |
| wit | mind, brain, thoughts |