pentaphyllon
From LSJ
Ἓν οἶδα, ὅτι οὐδὲν οἶδα → I know only one thing, that I know nothing | all I know is that I know nothing.
Latin > English (Lewis & Short)
pentăphyllon: i, n., = πεντάφυλλον, i. q. quinquefolium and pentapetes,
I five-leaved grass, cinque-foil, Plin. 25, 9, 62, § 109; App. Herb. 2.