WordWeb Online

1. Not prepared or vigilant
   "the blow caught him napping";
   - off-guard, off guard, off one's guard, off his guard, off her guard, off your guard

1. Have a short sleep, esp. during the day
   "She naps everyday after lunch for an hour";
   - catnap, catch a wink [informal], kip [Brit, informal], snooze, drowse, doze, zizz [Brit, informal]

See also: unready

Type of: catch some Z's [N. Amer, informal], sleep, slumber

Encyclopedia: Napping