ιδροκόπος
From LSJ
ἔγνω δὲ φώρ τε φῶρα καὶ λύκος λύκον → the thief knows the thief and the wolf knows the wolf, and thief knows thief and wolf his fellow wolf, set a thief to catch a thief
ο
αυτός που εργάζεται καλά, ο δουλευτής.
[ΕΤΥΜΟΛ. < ίδρος + -κοπος (< κόπος), πρβλ. δημο-κόπος, ξυλο-κόπος.