drowse off - change from a waking to a sleeping state; "he always falls asleep during lectures"dope off, doze off, drift off, fall asleep, flake out, nod off, drop offzonk out - fall asleep fast, as when one is extremely tired; "after the long drive, we zonked out and slept for 10 hours"
drowse off - change from a waking to a sleeping state; "he always falls asleep during lectures"