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. unable to think clearly or move steadily, for example during a fever or after drinking alcohol = dizzy
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"