Someone that's in your Myspace Friend's list who "stole" your music, pictures, etc and posted them on their "myspace page". There's a hidden rule in Myspace that you do not post the same exact song, pictures etc when someone has already "claimed" that song, picture, etc. This is a First-post-First-dibs standard. After the first person who posted the song, picture, etc. deletes it, even though you can put it up yourself, everyone will know who had it first.
Example one:

*Marisa signs on Myspace*

Marisa: I cannot believe this! Denisse put the same song as I did. She's such a Myspacejacker! I posted "Hips don't lie" first!

Example two

*Marisa signs on Myspace*

*Marisa's talking to Sal via Instant Messanger*

Marisa: Denisse Myspacejacked my song!

Sal: Yeah I know, don't worry! I knew who posted it first!

Marisa: Yeah but still... I had rights to it first.

Example three:

*Sal logs on Myspace, and visits his cousin's page*

Sal: Oh man! Mike posted that song first!! I wanted to put that song up, but I didn't know the name of it. I don't want to be a myspacejacker but... oh damn it.
by Denisse G August 5, 2006
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