This phrase is often used by people who identify with the "hipster" or "indie" crowd. The phrase literally means "ya dude" and sounds like its meaning if said fast enough. But of course such hipsters have to put a unique spin on an average phrase which causes people to turn and go "huh?" when they hear it.
Regular person: "Hey, have you heard of the band Animal Collective? They're awesome!"

Hipster person: "Chya doo. I heard of them ages ago."
by that1wookiee November 16, 2011
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