From Longman Dictionary of Contemporary Englishdoze off phrasal verbSLEEPto go to sleep, especially when you did not intend to SYN drop off, nod off I must have dozed off. → doze→ See Verb table
Examples from the Corpus
doze off• Sorry, I must have dozed off for a few minutes.• I was just beginning to doze off when the telephone rang. 