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3.
a girl is on the bottom and there is a guy fucking her and then there is a guy fucking him up the ass and another guy fuckng him up the ass on so on and so fourth.
cindy,john,bob,joe,and jared just did a sex train
by kalee/kristen September 09, 2006
 
1.
Referres to a sexual position involving 5 or more people standing in a line connected to each other in a sexual way
Hey,Nick, call Cassie, shanna, joe, and eric so we can have a sex train!!
by XxX MUCH LOVE XxX ~megan~ November 12, 2007
 
2.
The sex train is the term used to define an alpha male's female follower fanbase. The sex train is a term often used by highly desirable guys to describe all the guy's options in the realm of females. Everyone on the sex train is sexually attracted to said alpha male and has or would engage in sexual activity with him.
DutchEastIndiaCo: Dude that girl is totally on my sex train

YMKS: Your sex train is empty

DutchEastIndiaCo: **winks** all aboard!

*They proceed to procreate passionately*

Guy 1: You never get pussy

Guy 2: Are you kidding, the entire female population is up in my sex train, choo choo bitch.

Guy 1: Even my sister?

Guy 2: Handed that one a first class ticket yesterday!
by DutchEastIndiaCo. October 11, 2013