1.) A train that somehow gets off the tracks and manages to somehow still run without tracks...

2.) A word used when you are in distress.

3.) An annoying ass song that was writtin by Soul Asylum in the Mid-90's.

4.) A massive uncontrollable orgasm for a man. It is so massive that the semen is impossible to control and you end up shooting it across the room and splashing the wall with white goo.
1.)Runaway train victim: I was playing Tecmo Bowl when suddenly a runaway train went through my backyard and killed a guy living in my shed.

2.) (a guy gets hit in the head with a baseball) RUNAWAY TRAIN!!!!

3.) I was at my friend nasty nate's house when all the suddne he whipped out a Sould Asylum Cd so i had to kick his ass.

4.)OH MY GOD! RUNAWAY TRAIN!!!!! ::KApoW!:: ::splat::
by Fernando & Miguel July 23, 2004
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when you are fucking a girl from behing near a wall the let go of her hips and her head goes through the wall
"I gave her the runaway train and now her dad is making me pay for the wall"
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