The adjective is derived from Middle Englishgidi, gedy, gydy(“demonically controlled or possessed; crazy, insane; foolish, idiotic, ridiculous, unwise; unsure; (rare) dizzy, shaky; (rare) of an animal: crazed, out of control; a fool”)[and other forms],[1] from Old Englishgidiġ, gydiġ(“possessed by a demon or spirit, insane, mad”), from Proto-West Germanic*gudīg(“ghostly, spirited”, literally “possessed by a god or spirit”), from *god(“god”) + *-ig, *-g(suffix forming adjectives with the senses of being, doing, or having).[2] The English word is analysable as god + -y(suffix meaning ‘having the quality of’, forming adjectives).
The noun[3] and the verb[4] are derived from the adjective.
1665, Robert Boyle, “Occasional Reflections. Discourse XVIII. Upon a Giddiness Occasion’d by Looking Attentively on a Rapid Stream.”, in [John Weyland], editor, Occasional Reflections upon Several Subjects. With a Discourse about Such Kind of Thoughts, Oxford, Oxfordshire: Alex[ander] Ambrose Masson; and sold by John Henry Parker,[…], published 1848, →OCLC, section IV (Which Treats of Angling Improv’d to Spiritual Uses), page 277:
[W]hilst I was thus musing, and attentively looking upon the Water, to try whether I could discover the Bottom, it happened to me, as it often does to those that gaze too stedfastly on swift Streams, that my Head began to grow giddy, and my Leggs to stagger towards the River, into which questionless I had fell, if Philaretus had not seasonably and obligingly prevented it.
They see the roofs and argue about where the different churches are: Rathmines' blue dome, Adam and Eve's, saint Laurence O'Toole's. But it makes them giddy to look so they pull up their skirts …
2010 April 12, Bruce Kimmel, chapter 6, in “There’s Mel, There’s Woody, and There’s You”: My Life in the Slow Lane, Bloomington, Ind.: AuthorHouse, →ISBN, page 143:
Susan loved to drink wine, and I was not a drinker at all, so I'd just sit there and watch her drink glass after glass and get giddier and giddier.
[A]s vve pact along, / Vpon the giddy footing of the hatches: / Me thought that Gloceſter ſtumbled, and in ſtumbling, / Stroke me that thought to ſtay him ouer board, / Into the tumbling billovves of the maine.
VVilt thou vpon the high and giddy maſſe, / Seale vp the ſhip-boies eies, and rocke his braines, […]
1665, Robert Boyle, “Occasional Reflections. Reflection VI. Sitting at East in a Coach that Went Very Fast.”, in [John Weyland], editor, Occasional Reflections upon Several Subjects. With a Discourse about Such Kind of Thoughts, Oxford, Oxfordshire: Alex[ander] Ambrose Masson; and sold by John Henry Parker,[…], published 1848, →OCLC, section I, page 88:
[A]ll those changes, that are taken for the Giddy turns of Fortune's Wheel, shall serve to approach him the faster to the blest Mansion he would arrive at.
Povv'r like nevv VVine, does your vveak Brain ſurpriſe, / And its mad fumes, in hot diſcourſes, riſe; / But time theſe giddy vapours vvill remove; / Mean vvhile I'll take the ſober joys of Love.
From infancy through childhood's giddy maze, / Frovvard at ſchool, and fretful in his plays, / The puny tyrant burns to ſubjugate / The free republic of the vvhip-gig ſtate.
[T]hey oscillate, with a giddy and sickening motion, from one absurdity to another, and expiate the follies of youth by the heartless vices of advancing age.
Low lies the plant to whose creation went / Sweet influence from every element; / Whose living towers the years conspired to build, / Whose giddy top the morning loved to gild.
There, vvhile above the giddy tempeſt flies, / And all around diſtreſsful yells ariſe, / The penſive exile, bending vvith his vvoe, / To ſtop too fearful, and too faint to go.
As 'twere a hundred-throated nightingale, / The strong tempestuous treble throbb'd and palpitated; / Ran into its giddiest whirl of sound, / Caught the sparkles, and in circles, / Purple gauzes, golden hazes, liquid mazes, / Flung the torrent rainbow round: […]
The Biſhop, and the Duke of Gloſters men, / Forbidden late to carry any VVeapon, / Haue fill'd their Pockets full of peeble ſtones; / And banding themſelues in contrary parts, / Doe pelt ſo faſt at one anothers Pate, / That many haue their giddy braynes knockt out: […]
c.1593–1597, J[ohn] Donne, “[Satyres] Satyre I”, in Poems, […] with Elegies on the Authors Death, London: […] M[iles] F[lesher] for Iohn Marriot,[…], published 1633, →OCLC, page 325:
[I]n this ſtanding vvoodden cheſt, / Conſorted vvith theſe fevv bookes, let me lye / In priſon, and here be coffin'd, vvhen I dye; / […] / Here gathering Chroniclers, and by them ſtand / Giddie fantaſtique Poëts of each land.
[I]n briefe, ſince I doe purpoſe to marrie, I vvill think nothing to anie purpoſe that the vvorld can ſaie againſt it: and therfore neuer flout at me, for vvhat I haue ſaid againſt it: for man is a giddie thing, and this is my concluſion: […]
1631, Francis [Bacon], “VII. Century. [Experiments in Consort Touching the Insecta.]”, in Sylua Syluarum: Or A Naturall Historie. In Ten Centuries.[…], 3rd edition, London: […]William Rawley[…]; [p]rinted by J[ohn] H[aviland] for William Lee[…], →OCLC, paragraph 698, page 172:
It may be Gnats, and Flies, haue their Imagination more mutable and giddy, as Small Birds likevviſe haue.
They ſhall recover the miſattended vvords of Chriſt to the ſincerity of their true ſenſe from manifold contradictions, and ſhall open them vvith the key of charity. […] [M]any they ſhall reclaime from obſcure and giddy ſects, many regain from diſſolute and brutiſh licence, many from deſperate hardnes, if ever that vvere juſtly pleaded.
Such practices as Theſe, too groſs to lye / Long unobſerv'd by each diſcerning Eye, / The more judicious Iſraelites Unſpell'd, / Though ſtill the Charm the giddy Rabble held, […]
I can't bear her: she sets up to be natural and is only rude; mistakes insolence for innocence; says everything which comes first to her lips and thinks she is gay when she is only giddy.
I found him pokin' about the place on his own hook afterwards, an' I thought I'd show him the giddy drill. When I found he was so pleased, I wasn't goin' to damp his giddy ardour. He mightn't ha' given me the quid if I had.
I come by note to giue, and to receiue; / Like one of tvvo contending in a prize, / That thinks he hath done vvell in peoples eyes; / Hearing applauſe and vniuerſall ſhout, / Giddy in ſpirit, ſtill gazing in a doubt, / VVhether thoſe pearles[sic – meaning peals] of praiſe be his or no.
1767, “Dialogue I. Between Philip and Henry, Concerning the Importance of Early Religion.”, in The Friendly Instructor; or, A Companion for Young Ladies, and Young Gentlemen:[…], 3rd edition, volume II, London: […] J. Buckland,[…], →OCLC, page 4:
But I vvonder, that either theſe good men, or my mamma ſhou'd think, becauſe they may find it pleaſant vvho are come to maturity of judgment, that ſuch as vve vvho are in the gayeſt and giddyeſt part of life ſhou'd.
"I don't know what to do!" cried Scrooge, laughing and crying in the same breath; and making a perfect Laocoön of himself with his stockings. "I am as light as a feather, I am as happy as an angel, I am as merry as a school-boy. I am as giddy as a drunken man. A merry Christmas to everybody! A happy New Year to all the world. Hallo here! Whoop! Hallo!"
[…] Miss Phyllis Morgan, as the hapless heroine dressed in the shabbiest of clothes, appears in the midst of a gay and giddy throng; she apostrophizes all and sundry there, including the villain, and has a magnificent scene which always brings down the house, and nightly adds to her histrionic laurels.
VVide o'er the vvaſte the rage of Boreas ſvveeps, / And Night ruſh'd headlong on the ſhaded deeps. / Novv here, novv there, the giddy ſhips are born, / And all the rattling ſhrouds in fragments torn.
A nevv faſhion of apparrell creepeth no ſooner into vſe, but preſently he blameth and diſpraiſeth the olde, and that vvith ſo earneſt a reſolution, and vniverſall a conſent, that you vvould ſay, it is ſome kinde of madnes, or ſelfe-fond humor, that giddieth his vnderſtanding.
1634, T[homas] H[erbert], “A Discourse of the Life and Habit of the Persians at this Present”, in A Relation of Some Yeares Trauaile, Begunne Anno 1626. into Afrique and the Greater Asia,[…], London: […]William Stansby, and Jacob Bloome, →OCLC, page 151:
[T]he footmen vſe it [opium] too as a preſeruer of ſtrength, and vvhich is ſtrangeſt, ſo giddies them, that in a conſtant dreame or dizzineſſe, they run ſleeping not knovving vvhom they meet, and yet miſſe not their intended places: […]
And indeed her ovvn little head vvas ſo giddied vvith this vvonderful elevation; […] that had ſhe not really been one of the prettieſt figures that can be imagined, ſhe vvould have been inſufferable.
1865, Ouida [pseudonym; Maria Louise Ramé], “Thalassis! Thalassis!”, in Strathmore: A Romance[…], volume III, London: Chapman and Hall,[…], →OCLC, page 275:
[T]he hiss of the plunging shot deafening their ear and giddying the brain, with life and liberty beyond, and behind a doom more dread than death, they fled on through the heavy, breathless night.
[B]y chance, a sudden north-wind fetch'd, / With an extreme sea, quite about again / Our whole endeavours, and our course constrain / To giddy round, and with our bow'd sails greet / Dreadful Maleia, calling back our fleet / As far forth as Cythera.