The act of a man shoving his arm in his ladies anus, elbow deep. Upon pulling it out, one will create the illusion of a tunnel for an asshole.
Melvin: Hey Geoffrey what is the matter? Your arm looks at little sore...

Geoffrey: Yah its sore Melvin, I had a serious case of Tunnel Arm last night.
by A. Giacs September 9, 2018
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