catch someone napping

catch (one) napping

1. Literally, to discover that one is sleeping when one is not supposed to be. A: "Why was Bill fired?" B: "I heard they caught him napping at his at his desk."
2. By extension, to exploit or capitalize on one's inattention. We were able to sneak into the building because we caught the security guard napping. I scored a goal after I caught their defenseman napping.
See also: catch, nap
Farlex Dictionary of Idioms.

catch someone napping

(of an action or event) find someone off guard and unprepared to respond. informal
See also: catch, nap, someone
Farlex Partner Idioms Dictionary
See also:
  • cooking for one
  • drive (one) out of office
  • force (one) out of office
  • force out of office
  • give (one) (one's) head
  • give head
  • give somebody their head
  • give someone their head
  • 1FTR
  • as one door closes, another (one) opens