First recorded around the time of the norman conquest of 1066.
Mainly used back then in honor of William the conqurer as it also originates from the name (french origin) William.
Gilliam is the correct spelling of the american surname where as there are many other spellings which were obtained by derilict gypsy prostitutes in england and old time ghetto dwellers of barbados in the 1600's.

Gilliam:(pronounced Gil-am) is best defined as the greatest man ever created. The inventor of the french dip,the haitian fruit basket, and the mongolian teepee. All Gilliams are underworld leaders and have more power than your local government. Very intelligent, and very attractive...Gilliam men exceed expectations in all catagories. Gilliam women inherit the same traits.

Famous Gilliams include:Terry Gilliam,Joe Gilliam,William E. Gilliam,and Scott M.Gilliam
what do you call a Gilliam that cant hold his liquor?
by HarmonyKoruption February 2, 2010
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One of the greatest, most twisted directors of all time, who has to date made criminally few films and is plagued by terrible luck. Best known for his Monty Python animations, "Brazil", and "Fear and Loathing in Las Vegas", but actually the rest of his films are equally brilliant.
I never thought that Terry Gilliam could get even more unlucky after what happened in "Lost in La Mancha", but I'm reconsidering after Heath Ledger's death.
by prettymaryk March 23, 2008
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Possessor of an extremely large reproductive organ. Astronomically superior intellect in comparison to his peers. six foot two, handsome, and confident. Also, anything is possible when you lie.
There's no way that's true, that's such an Alex Gilliam.
by BgAg25 February 17, 2017
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jon gilliam is the modern rambo. Ryan is his sidekick. He runs around naked in football cleats with his big maltball nipples, screaming, "Get off my shit!" In his crappy apartments with his fat ass mom who's got a bearded clam when she walks, "Squishy, Squishy."
Jon Gilliam is rambo, and a quim.
by Tony Tuthill November 18, 2006
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Patrick is a savage a complete fucking savage he's the kinda guy you could smoke weed with and not get in trouble he is the coolest person you will ever meet he has a awesome personality and is so energetic he is the kinda guy you want as a friend he's savage he's a beast and he will stab you if you touch his food! But overall Patrick is a great guy and a great friend
Man that guy stabbed that dude and he didn't get in trouble what a Patrick Gilliam
by Joe Pats Best Friend September 6, 2016
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