If you feel light-headed, you feel rather unsteady and strange, for example because you are ill or because you have drunk too much alcohol.
例句
If you skip breakfast, your blood sugar level will drop and you will probably feel light-headed.如果不吃早餐，血糖含量就会降低，你很可能会觉得晕眩。
英英词典释义
Adjective
1. weak and likely to lose consciousness;
"suddenly felt faint from the pain""was sick and faint from hunger""felt light in the head""a swooning fit""light-headed with wine""light-headed from lack of sleep"
2. lacking seriousness; given to frivolity;
"a dizzy blonde""light-headed teenagers""silly giggles"