(largely obsolete, now only nonstandard) Difficult to believe; incredible.
1984, Supreme Court of Illinois, opinion in People v Terrell, 459 N.E.2d 1337, quoted in David C. Brody, James R. Acker, and Wayne A. Logan, Criminal Law, Jones & Bartlett Publishers (2001), →ISBN, page 564,
Faced with these facts, we find it incredulous that [the] defendant had any intent other than the armed robbery of the service station.