Английский словарь американских идиом - dead on one's feet

{adv. phr.}, {informal} Very tired but still standing or walking; too tired to do more; exhausted. * /Jimmy never leaves a job unfinished. He continues to work even when he's dead on his feet./ * /After the soldiers march all night, they are dead on their feet./ Compare: DEAD TIRED, WEAR OUT(2).