13th base

Sex with your boss, professor, or another person you have no business fooling around with . . .

"I did not have sexual relations with that woman . . . it was just 13th base!" -- Bill Clinton

by Scylla June 29, 2006

13th base

(male) when you have intercourse with a female and you end up getting warts, aids, and every other STd you can think of.

Man this girl took me to 13th base and now my life is over!

by Will Deshazo June 11, 2006

13th Base

having sexual intercourese with your partner while wearing Sherlock Holmes hats, smoking pipes and completing a crossword in under 10 minutes.

I got to 13th Base with the wife yesterday and she came allover my deer stalker

by sergio97 January 1, 2011

13th Base

When you have sex with an animal and a person at the same time.

"Dude, that weird dude next door got to 13th base last night."

by Mr. Supotco November 13, 2015