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1.
Pronounced 'Kee-on'

To Keian someone is a verb meaning to promise or act like you are going to do something, see something, go somewhere etc... and then to not full-fill said promise.

It can also mean to be consistently unreliable.

Past tense - Keian'd
Person1:"Hey man, is Tommy coming to the party?"
Person2:"Yeah, he said he'd come this morning.."
*Half way through the party*
Person1:"I think Tommy totally Keian'd you man.."
Person2:"Yeah, he's so unreliable"
by Piepai May 24, 2010