"napping" in the verb sense
1. nap, catnap, catch a wink
take a siesta
"She naps everyday after lunch for an hour"
"napping" in the adjective sense
1. napping, off-guard, off guard, off one's guard, off his guard, off her guard, off your guard
not prepared or vigilant
"the blow caught him napping"
"caught in an off-guard moment"
"found him off his guard"
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License