<p><strong>Adjective</strong></p><ul><li>gid·di·er, gid·di·est.</li><li>affected with vertigo; dizzy.</li><li>Synonyms: vertiginous, lightheaded.</li><li>attended with or causing dizziness: a giddy climb.</li><li>frivolous and lighthearted; flighty: a giddy young person.</li><li>Synonyms: vacillating, inconstant, fickle, mercurial, volatile, unstable.</li></ul><p><strong>Verb</strong></p><ul><li>(used with or without object) gid·died, gid·dy·ing.</li><li>to make or become giddy.</li></ul>