catch (one) 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

 and catch someone off balance; catch someone up short
to come upon someone who is unprepared; to surprise someone. (See also asleep at the switch.) The enemy soldiers caught our army napping. The thieves caught the security guard napping. I didn't expect you so soon. You caught me off balance. The teacher asked a trick question and caught me up short. The robbers caught Ann off balance and stole her purse.
See also: catch, nap
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

catch napping

Surprise, take unawares. This term is often used in the passive, as in The United States was really caught napping the day the Japanese bombed Pearl Harbor. It originated in the mid-1500s as to be taken napping. Also see under off guard.
See also: catch, nap
The American Heritage® Dictionary of Idioms by Christine Ammer.

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

catch somebody ˈnapping

(informal) find somebody not prepared or not paying attention, and perhaps gain an advantage over them as a result: Chelsea’s defence was caught napping in the final moments of the game when Jones scored his second goal for Liverpool.
Nap means ‘sleep’, usually for a short time and especially during the day.
See also: catch, nap, somebody
Farlex Partner Idioms Dictionary

napping, to be caught/catch

To be surprised off guard, taken unawares. This term began life in the sixteenth century as to be taken napping. “Take Nappynge as Mosse toke his Meare” was the title of a 1569 ballad. The term was included in John Ray’s proverb collection of 1670, in which Ray commented, “Who this Moss was is not very material to know. I suppose some such man might find his mare dead, and taking her to be only asleep, might say, ‘Have I caught you napping?’” Yet Shakespeare and other sixteenth-century writers used the phrase in the modern sense of taking someone unawares; “Nay, I have ta’en you napping, gentle love,” Tranio says to Bianca (The Taming of the Shrew, 4.2).
See also: catch, caught
The Dictionary of Clichés by Christine Ammer
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