ὀμώμοκα

From LSJ

οὐκ ἂν λάβοις παρὰ τοῦ μὴ ἔχοντος → you can't take from one who doesn't have, you can't squeeze blood out of a turnip, you can't get blood out of a turnip, you can't get blood from a stone, you can't get blood out of a stone

Source

French (Bailly abrégé)

v. ὄμνυμι.

Greek (Liddell-Scott)

ὀμώμοκα: πρκμ. τοῦ ὄμνυμι.

Russian (Dvoretsky)

ὀμώμοκα: pf. к ὄμνυμι.