Basically anything that is something.

May be used as a noun, adjective, verb or exclamation/interjection. May replace almost any word. Use as conjunction or adverb may be controversial and frowned-upon by members of the population who prefer to be able to interpret/comprehend speech.
Person 1 - Hey John, do you want me to opay down to the store and grab some opays? I think we're running low.

Person 2 - Opay! Yeah bro it's about time. I haven't been able to opay an opay for like opay weeks now, it sucks.

Person 1 - You want me to opay any other opays while i'm opaying down at the opay?

Person 2 - Yeah opay an opay and some opays for opaying the opay opay. Also opay an opay for the opay opay for jogabonitoi opay opay opay. Opay!
by Dshar December 24, 2012
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A common misuse for "Okay", often used in conversations between people.
Ralph: Yo dog, lets party.
Ronald: Oh, opay!
Ralph: Oh, Oh, opay!
by RDizzieofftheHizzie April 19, 2011
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The japanese word for breast(s). don't say opais because that doesn't work. the japanese don't have plural words. the japanese specify the amount of something.

for young children or babies it means milk.
terry: i need a bigger bra.
sarah: i wish i had your opai!
terry: ha! you have chisai opai!
by Beverly Jones April 4, 2009
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