How to sign: having or causing a whirling sensation; liable to falling
"had a dizzy spell"; "a dizzy pinnacle"; "had a headache and felt giddy"; "a giddy precipice"; "feeling woozy from the blow on his head"; "a vertiginous climb up the face of the cliff";
Similiar / Same: giddy, woozy, vertiginous
How to sign: lacking seriousness; given to frivolity
"a dizzy blonde"; "light-headed teenagers"; "silly giggles";
Similiar / Same: airheaded, empty-headed, featherbrained, giddy, light-headed, lightheaded, silly