1 definition by Keith B.

A man's worse nightmare. While frequent in driving, it can often occurs spontaeously when temperatures are above 58 degrees Fahrenheit. Basically from March to October you pray that no girl accidently brushes against your back and feels your moist lumbar. Likewise wearing t-shirts that clearly show your back sweat is also not advised.
"Hey man it's suppose to reach 60 today!"
"Oh crap man, back sweat is coming, i can feel it."
by Keith B. May 12, 2006
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