A game in which major league baseball players are drafted to fill a fake roster. Different leagues have different settings but essentially you get rewarded when players on your team do good (such as striking out batters or hitting a home run) and penalized when they play poorly (such giving up 5 runs or striking out).
Fantasy baseball players are usually hardcore baseball nerds and/or stat heads. It is taken extremely seriously and causes extreme mood swings.
John loved the Boston Red Sox, so he felt dirty for selecting Derek Jeter as the SS for his fantasy baseball team.

I haven't slept in 3 days, my fantasy baseball draft is coming up and I need to study
by Will.I.Am2121 October 8, 2010
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In fantasy baseball competition, "Rebuild Mode" is a term used for a shitty team trying to save face.
My team sucks this year because we are in Fantasy Baseball Rebuild Mode.
by velcro June 30, 2012
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