nod off

verb

1. informal,  (intr, adverb) to fall asleep

Idioms and Phrases

Fall asleep momentarily, doze, as in Grandma spends a lot of time in her rocking chair, nodding off now and then. This expression alludes to the quick involuntary dropping of one's head from an upright position when drowsy or napping. The verb nod alone was so used from the mid-1500s. Also see drop off, def. 1.

Related Words

• bed down www.thesaurus.com
• doze 
• fall asleep 
• languish 
• relax 
• snooze