Definition of Lightheaded

Adjective: lightheaded ,lIt'he-did

Weak and likely to lose consciousness
"suddenly felt lightheaded from the pain";
- faint, light, swooning, light-headed
Lacking seriousness; given to frivolity
"a lightheaded blonde";
- airheaded, dizzy, empty-headed, featherbrained, giddy, light-headed, silly