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1 definition by Rerakudeshigunesu

1. adv. - shortened variant of "probably"; in all likelihood; likely. Typically used online.

1. You should prolly used "prolly" only in instant messaging. Using it in real life sounds kinda lame-o. But I prolly won't follow this rule anyhow...

Usage Notes: Using "prolly" and other forms of internet slang do not make one an idiot, unlike many of the arrogant people here have established. It is used simply because it is quicker to type "prolly" than "probably".
by Rerakudeshigunesu February 10, 2008