1 definition by ewitsmelala

used to say, "hold up" or "wait a minute" or "thats not true" or to express disbelief.
1. A loud girl, Joanna is talking to a boy, Liam for the first time:
Liam: you seem really quiet Joanna
Joanna: Back up the Train! I never shut up!

2. Joanna is talking to her friend Lisa later that day:
Joanna: so I talked to Liam today!
Lisa: BACK UP THE TRAIN YOU LUCKY DUCK!

3. Lisa is talking to Rebecca later
Lisa: Rebecca you're kinda annoy-
Rebecca: Backup the train & don't let that thought out of the station!
by ewitsmelala January 29, 2010
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