Green’s Dictionary of Slang

1. (also gack, gak, gheck) an odd, eccentric-looking person.

1576		Tyde taryeth no Man in Collier (1863) II 29: And though I haue attire both costly and gay, / Yet vnlesse it be new, I shall haue but a geck.
1600		Shakespeare Twelfth Night V i: Why have you suffer’d me to be imprison’d [...] And made the most notorious geck and gull that e’er invention play’d on?
1636		W. Davenant Wits I i: Can the daughters of Brabant Talk thus when Younker-gheck leads ’em to a stove?
1822		R. Nares Gloss. (1888) I 353: geck. a Fool [...] a jest, or a subject of ridicule.
1858		Broadway Omnibus (N.Y.) 1 Nov. 2/2–3: THE GECKS AND GULLS, OR KNAVES AND FOOLS OF NEW YORK.
1859		‘George Eliot’ Adam Bede (1873) 82: I’d never marry a man as had got no brains; for where’s the use of a woman having brains of her own if she’s tackled to a geck as everybody’s a-laughing at?
1997–2000		College Sl. Research Project (Cal. State Poly. Uni., Pomona) 🌐 Geck 1. (noun) A unique individual who is oblivious to the fact that they are so different. (Short for gecko.).
2001		G. Coughlan Everyday Eng. and Sl. 🌐 Gack (n): refers to a foolish or stupid person. Can also be pronounced ‘gackawacka’, or ‘gacky’ (a). ‘Wise up ya gack ye.’ ‘Those shoes are gacky looking.’.

2. (Ulster) a person who tells tales behind another’s back, a gossip.

1997

Share Slanguage.

3. a person who uses LSD.

1997–2000

College Sl. Research Project (Cal. State Poly. Uni., Pomona) 🌐 Geck [...] 2. (noun) A person who uses l.s.d.