Webster's Revised Unabridged Dictionary · 1913

Giddy

Giddy , adjective

[Old English gidi mad, silly, Anglo-Saxon gidig, of unknown origin, compare Norw. gidda to shake, tremble.]

1.
Having in the head a sensation of whirling or reeling about; having lost the power of preserving the balance of the body, and therefore wavering and inclined to fall; lightheaded; dizzy.
By giddy head and staggering legs betrayed. — Tate
2.
Promoting or inducing giddiness; as, a giddy height; a giddy precipice. — Prior
Upon the giddy footing of the hatches. — Shakespeare
3.
Bewildering on account of rapid turning; running round with celerity; gyratory; whirling.
The giddy motion of the whirling mill. — Pope
4.
Characterized by inconstancy; unstable; changeable; fickle; wild; thoughtless; heedless.
Giddy, foolish hours. — Rowe
Giddy chance. — Dryden
Young heads are giddy and young hearts are warm. — Cowper

Giddy , intransitive verb

To reel; to whirl. — Chapman

Giddy , transitive verb

To make dizzy or unsteady. [Obsolete]