Knee knocker

1) A term used by sailors for the jamb of a water-tight door. A water-tight door's opening is about 20 inches above walking surface.

2) A term used by hot-rod enthusiasts for after market items mounted to the bottom of a dashboard assembly. (ie. Tachometers, Nitrous Oxide switches, etc.)

A term, which came about in the 1800's, however became popular with soldiers in the Second World War.

A knee knocker is a specific act of casual sex, usually performed in an alley beside or behind a pub/bar/tavern.

The act is performed standing up, with the woman secured against a wall with a combination of the mans upper body and holding her buttocks. The womans legs, usually wrapped around his waist.

This unusual position, whilst having sex results in the knees of the male regularly knocking together (often with some force), hence the term.

Also refer to the term 'knee trembler'.

Knee Knocker is a type of weapon that is shorter than a baseball bat, but long enough to swing at someone's knees. A Knee Knocker will be short enough to be portable, but long enough to reach at the knees of someone and possibly break their legs, if swung hard enough.

Often times, you'll see this being used as a self defense weapon and being at a fixed length. You can find telescoping ones and even some that can be specially designed to impact with the most amount of energy.

an old womans saggy tits that hang down and knock against her knees with every step she takes. some men find this erotic and very hot sex can stimulate a penis to pentrate through the knee knockers and enter the vagina.

a very well endowed male

Stretched, low hanging testicles.

When you take your dick, and put it in between the girls calve, and hamstring (where they meet when knee is bent) and proceed to screw it.