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2.
a friend who has smashed with the same wizard sleeve as you.
did you fuck sara too? man, you're my tunnel buddy now.
by t_piddy December 11, 2007
 
1.
When guys have slept with the same girl on different occasions.
Are you serious, you slept with Sara too. You know that makes you and Frankie Tunnel Buddies!
by Dick Shipton March 09, 2008
 
3.
When two male individuals have sex with the a female within a short period of time. This word became popular in the Howard Stern Show
Having sex with these chicks last night made us official Tunnel Buddies
by DeceptionDV February 03, 2009
 
4.
When two gay men share a chronic addiction to anal fornication. Habituation of anal sex will eventually scar one's anus, marking one as a permanent "Tunnel-buddy."
"Oi, faggot, I heard you were officially labeled as a Tunnel-buddy by Anderson Cooper."
by xingm8y May 05, 2014
 
5.
slang - Homosexual man (i.e. the catcher)
That over there is walking like he's got something up his ass, he's got to be a tunnelbuddy
by Tom Thamuz September 01, 2003