Also found in: Thesaurus, Legal.
1. So implausible as to elicit disbelief; unbelievable: gave an incredible explanation of the cause of the accident.
2. Astonishing, extraordinary, or extreme: dressed with incredible speed.
[Middle English, from Latin incrēdibilis : in-, not; see in-1 + crēdibilis, believable; see credible.]
in·cred′i·bil′i·ty, in·cred′i·ble·ness n.