'lightheaded' definitions:

adjective

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" [syn: faint, light, swooning, light-headed, lightheaded]

adjective

Lacking seriousness; given to frivolity; "a dizzy blonde"; "light-headed teenagers"; "silly giggles" [syn: airheaded, dizzy, empty-headed, featherbrained, giddy, light- headed, lightheaded, silly]