honk (someone’s horn), v. — Green’s Dictionary of Slang

honk (someone’s horn) v.

[the image of squeezing or ‘honking’ an old-fashioned horn or hooter]

(US) to squeeze the male or female genital area or female breast, thus crotch honker, a groper, one who masturbates gay males.

1970		J. Wambaugh New Centurions 186: ‘Honest to God, she honked my horn [...] Gave it two toots with a thumb and forefinger’ [ibid.] 197: ‘[Y]ou don‘t have to let a man grab your joint. If it looks like he’s making a move to honk you, just grab his hand and he’s busted.
1975		J. Wambaugh Choirboys (1976) 254: He had just been ‘honked,’ as the vice cops called it, in a public place.
1990		S. Morgan Homeboy 16: ‘What’s the forecast?’ Joe asked, reaching to honk a Schwartzian hooter.
2021		J. Ellroy Widespread Panic 57: A fruit honked him at Grauman’s Chinese. He bit the guy’s nose off [ibid.] 84: ‘Bernie quit honking me — get your fat paws off my tits’.
2023		(con. 1962) J. Ellroy Enchanters 238: He worked the vice traps [...] and entrapped crotch honkers wholesale.