The word "loony" comes from the retarded superstition that staring at the moon will make you batshit crazy. It can mean one of 2 things:
1)Someone who disagrees with you, and who you do not wish to speak to or listen to. This term can be used by nancy boys and douchebags such as fundies, generally to refer to lib'rals.
2)Someone who is demonstrably delusional or psychotic. Often these people will disguise their psychosis as a political ideology, generally blaming various groups of scapegoats for all their problems based on negligible or nonexistent evidence.
Famous current loonies include: Ann Coulter, John Ashcroft, Rush Limbaugh, Jerry Falwell, Pat Robertson, Osama bin Laden, and all other fundies, Nazis, and people involved with (or seriously believing the rhetoric of) the Church of Voodoo Pharmacology.

The most common relatively sane person to be an alleged loony is Michael Moore, who contrary to Republican beliefs is not actually insane, but simply obese and incoherent.
by jazzriff October 12, 2005
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An alcoholic pervert with shit feet who speaks to himself who where’s a shirt to work and drinks chicken soup
Does the loony run the insitu or does the insitu run the loony?
by Asdf ;lkj June 27, 2018
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A guy who's trying to get with a female but doesn't know she's pretending to like him for the fun of how stupid he looks for thinking she really likes him.
Did you see when I took Ben's glasses and playfully ran away. He thought I was flirting. HA HA! What a loonie man.
by Moni_Martini September 23, 2009
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Slang for a Canadian Dollar coin, has a picture of a duck on it. Ducks are cool. Oh yea, the reigning British monarch is there too.
Feel like filling a sock full of loonies and beating some Canadians?
by Tyler Berry September 28, 2005
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Someone who thinks they are effected by the phases of the moon - especially a full moon
You must be a loony
by Mike P January 21, 2004
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An insane asylum or the psychiatric ward of a hospital for the mentally ill. Often used as an offensive term.
"They made me go to the loony bin for seeing visions of God! Can you believe them?!?" said the guy to another guy.
by sniff'n'free July 13, 2013
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