I've got an old Dictionary program I got in a PC magazine cover disc in '94 (it's still a great little program) – the Oxford Reference Shelf – and two of its definitions amuse me:
hackneyed adj. (of a phrase etc.) made trite by overuse.
which doesn't look too bad, until you look up "trite":
trite adj. (of a phrase, observation, etc.) hackneyed. tritely adv. triteness n. [Latin tero trit- rub]
So, apparently, "hackneyed" means "make hackneyed by overuse"...