eleventh finger 

A sexual manouever in which a man, while fingering a woman outside of her field of vision, inserts his penis without announcing he is doing so. The act is generally employed as a means to commence intercourse with a hesitant (but willing) partner.

The term "eleventh finger" can also simply be slang for penis.

Chris: Well, she was kinda riding the fence about having sex with me. Since she never said no outright, I gave her the eleventh finger, and that was that.

Kevin: nicely done, sir.

eleventh finger by Cosmo July 12, 2006

Eleventh Finger 

The penis.

Originated from the third episode of the show 'Family Guy'

"I've sprouted another finger. Counting the one from yesterday, I'm up to 11. " - Stewart Gilligan Griffin

I showed her my eleventh finger under the bleachers.

Eleventh Finger by lbeesntdeirx November 5, 2013

Eleventh finger 

Another name for penis

That man has such a small eleventh finger.

Eleventh finger by Raquelkenna August 28, 2018