the mind > mental capacity > lack of understanding > stupidity, dullness of intellect > [adjective] > in appearance (4)
Of the eye: Dull, vacant of expression. Also in combination fishy-eyed adj.
Having a round, flat face or a blank expression; stupid.
resembling a cabbage in appearance; (also in extended use) naive, gullible (frequently in to be not as green as one is cabbage-looking: see green…