The act of seaching the net for and subsequently uploading a photo of an ugly woman to Facebook and tagging a female victim stating the said ugly woman is in fact the victim.

Typically used as an act of revenge, or to simply cause offence to the victim.

Effective way of culling your Friend List in a more enjoyable manner.
Mabel: I seriously need to eliminate some 'friends' on Facebook, but it's such a boring job.
Vera: Just Hag Tag a few people. They'll be so offended, they'll de-friend you thus saving you a job.

Bob: She's only gone an told everyone I was a lousy shag.
Dave: Ah, dude, that sucks.
Bob: S'all right. I Hag Tagged her. That'll teach the vile cow.
by Bowchickkawowwow January 18, 2011
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