A man who frequents prostitutes (John), but materbates on, or is masterbated by (handcock) the prostitute, rather than having sex with her, as a means of avoiding STDs.
YOU: Hey, John, do you wanna go to the bar?

YOUR BUDDY: No, I'm going to see Sharin' Cocks, that ho down the road.

YOU: Aren't you afraid of AIDS?

YOUR BUDDY: No, I'm a John Handcock.
by Sex Ed December 07, 2006
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while cumming onto someones face you write your name with the semen. This definition makes sense because your hand is on your cock and there was some guy who signed some piece of shit called the declaration of independence and now he is some hot shot for knowing how to spell his own name, but thats another story.
After fucking for a while max finished it off with a john handcock to commemorate the experience.
by MW52 December 06, 2006
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v.it., The act of male masturbation whilst seated on a toilet. This term originates from a play on words; one's hand is on one's "cock", thereby conducting the act of masturbation. As this occurs, one is also seated upon a "John", or toilet. Often the physical stimuli of the act itself is inhanced by pressure on the prostate from passing feces.
Jonathan takes fifteen minutes every Saturday morning to treat himself to a John Handcock after checking the markets in the Tribune.
by Spack McDrack November 26, 2004
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The act of jerking off, or stroking your cock while engaging in intercourse. The act has one, two, and three finger variants; however, the three finger variant is the original form. Performed by inserting your pointer finger, up to and including your middle and ring fingers, into the woman's vagina under the shaft of your penis. Then gripping around the shaft leaving the thumb exposed over the top near the clitoris. Once held into position you proceed to stroke yourself while performing intercourse.
Ex 1:
Man A to Friend A:
"Last night was wild, I even gave her the Ol' John Handcocker."

Ex 2:
"Angelique's pussy was so loose and wet I had to give her the ol' John Handcock to finish us off."
by TeoDee September 12, 2017
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When ur finished fucking a girl, pull out, cum on her chest, and use ur Hands to sign your name on her chest.
After I paid her a Ben Franklin, I gave her a John HandCock.
by The Kid's Killin November 12, 2007
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