Commenting or posting on someone's facebook post where you don't know the person.

After the post, the invader writes INVADED! to let everyone know they've been invaded.
Augie puts picture up of himself. Two friends comment, one person (Danny) unknown to all, invades:

Jenny - Aww u look awesome!
Chris - Where did you get that sword?
Danny - You look like a young Marvin Hamlisch :D. INVADED!

That was a facebook invade.
by MDMC January 14, 2011
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