Irish slag
A resident of Ballyshannon, County Donegal, Ireland.
Also, a word frequently used by residents of above town, usually meaning the same as American term "dude".
John's the biggest sham you'll ever see.

Sham! Long time no see.
by Shambert April 5, 2008
Originally used in the U.S. Army to describe the act of pretending to work in order to avoid actually working.
"Specialist Little is the Sham Master. He can take 3 hours to wipe his ass and look busy the whole time."
by W. A. Rice October 29, 2004
Irish slang (mostly used in the southern County of Cork, famous for its plethora of slang terms)

a "sham" is primarily the term used to describe a young male knacker, specifically the ones who walk around with a chip on thier shoulder, thinking they own everything in sight, and that they are the greatest thing on god's green earth

it can also be used to show genuine praise, much to the same affect as "the shit".
{insult}
Dave - " Check out the sham across the road "
Kevin - " what a twat ! "
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{praise}
"my new shoes are the sham"
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{sarcastic}
billy - " like my new top ? "
joe - " you look like a right sham... "
by Emperor Bubba April 5, 2005
The American two-party political system is a sham.
by d;slfsdlk;fj November 8, 2003
noun. A male. Especially a member of the working class. Similar in meaning to the UK word chav. Often used by the working class to refer to eachother.
"How's it goin, sham?"
"Watch out that guy's a total sham."
by The Cardinal April 4, 2005
A respected member of the community in the urban district of Tuam, County Galway, Ireland. Often confused with the terms chav and knacker.
"He's a sound oul sham."

"Lamp his gills, i'm not wide, is he a sham?"
by Mike Flaherty December 28, 2007