Word History: Though little trace of a divine provenance can be discerned in its modern meaning, giddy is derived from the same ancient Germanic word (*gudam) that has given us the word God. The Germanic word *gudigaz, formed from the word *gudam, meant "possessed by a god." Such possession can be a rather unbalancing experience, and so it is not surprising that the Old English descendant of *gudigaz, gidig, meant "mad, possessed by an evil spirit," or that the Middle English development of gidig, gidi, meant the same thing, as well as "foolish," "mad (used of an animal)," "dizzy," and "uncertain, unstable." Our sense "lighthearted, frivolous" represents the ultimate secularization of giddy.