light-headed

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”

lacking seriousness; given to frivolity

• “a dizzy blonde”
• “light-headed teenagers”
• “silly giggles”