Definition
to start to sleep, often without meaning to, especially unintentionally
打瞌睡
I accidentally nodded off in my seat during the long flight.
我在漫長的飛行中不小心在座位上睡著了。
He nodded off during the meeting because he had stayed up late working last night.
他昨晚熬夜工作，結果在會議中睡著了。
I often nod off unintentionally while watching TV.
我經常在看電視時不經意地睡著。