from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Slang An old person, especially an eccentric old man.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A male person.
- n. An old person, usually a male.
- n. A device for boiling water for such domestic uses as heating or washing; a boiler. The normal spelling is water geyser.
from the GNU version of the Collaborative International Dictionary of English
- n. A queer old fellow; an old chap; sometimes, an old woman.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a man who is (usually) old and/or eccentric
Probably alteration of dialectal guiser, masquerader, from Middle English gysar, from gysen, to dress, from gyse, guise, fashion; see guise.(American Heritage® Dictionary of the English Language, Fourth Edition)