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2.
When a trucker has been on the road for many days needing release of his male functions. Similar to blue balls, he needs to cum!
Damn baby I've been on the road for 13 days, I really have a case of diesel dick!
by wanda November 27, 2004
 
1.
The Inevitable unwanted erection that occurs approximately 23 seconds before your stop on the bus/train, and causes you to walk off bent double

Also travel fat,traveller's marrow
No, i'm not carrying a gun. I'm afraid that its just an acute case of diesel dick.
by Prizwig April 30, 2004