The act of being random, spastic, and unpredictable. When Erin-ing occurs, one can a few things:
1) Ignore it
2) Join it
3) Question it

The Erin-ing behavior will eventually end (usually when the victim get tired, hurt, or runs out of caffeine/sugar)

Do NOT try to Erin-ing behavior from happening. If so, it will result in terrible consequences.
Person 1: Why is that chick throwing pineapples?
Person 2: Don't worry about her. She is Erin-ing

Person 1: Dude! This party is boring!
Person 2: I know! We need to get some Erin-ing is here!
by blondegirl544 December 29, 2011
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