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When a guy and a girl are going out and the girl just hangs all over the guy. The guy doesn't care. The girl is useless and hangs there much like a keychain to a backpack.
girl: (hugs boy)
boy: meh

observing girls: god, that girl is such a keychain
by TangoMaureen December 10, 2005
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Aug 11 Word of the Day
A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.
"My boyfriend has a total case of brain worms. He told me the cat was bugged so the Feds could listen in on us having sex..."

or

"You totally stumbled over that entire sentence. Can't speak English all of a sudden? What, do you have brain worms?"
by _Jez_ October 03, 2009
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2
The visible print made by a man's penis on the front of the pants. The phallic formation seen through a man's trousers, shorts, or jeans. See also DICK PRINT

Plural: keychains
We were too distracted by the keychain at the amusement park to really enjoy the roller coaster.
by q.wsmith March 31, 2010
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3
One of the many items I have shoved up my ass.
Emily: I shoved a key chain up my bootyhole
Beth: Haha...I lost my keychain a while ago....
by Helen's corndog March 02, 2020
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4
In the act of threesome with two males and one female. A keychain happens when one male drives his penis in the females vagina, as the other male drives his penis in the females anus all at the same time. In which creates an effect of a keychain.
"Dude we keychained this bitch last night!"
by AccurateDefinitions4578 January 12, 2015
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