A hooker, whore, prostitute. Term usually used to describe whores in big cities such as New York and Chicago because they stand and wait for customers in traffic tunnels.
"Hey Dad, Let's go into the city and check out the tunnel bunnies; you're paying this time!"
by SeanH October 05, 2004
A person who digs a tunnel into a country illegally from another country
Imagration just caught a bunch of tunnel bunnies coming into the country illegally
by JOKER024 February 19, 2011