What is Thumbin'?
1.
An action in which one does not stop texting
"I am trying to talk to her but she keeps thumbin' on her cell phone"
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2.
a dance move similar to the choo choo but done with fists with the thumbs up while leaning back from the waist to give the impression of being laid back
A typical night out for James and Bondy would involve a thumbin' session at the Bull
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3.
n. the use of the thumb to stimiluate the female anus during sexual intercourse; applied while in doogy style.
Ooh daddy, keep thumbin, 'cause I'm comin'!