A threat to put your dick in something/someone.
Slap a dick in it.To let a girl know she is fine, as in "Damn Megan Fox is sexy, I'd love to "Slap a dick in it"!
Or to piss off a dude(past tense)"Saw your mama last night, yep, I bent her over and "slapped a dick in it".
When someone really means it, when they understand that 'getting a dick in it' is of much importance, add the word straight, as in "That girl in the miniskirt keeps bending over, and she's wearing no panties, and she has a bottle of 'anal glide' in her hand...I'm gonna have to "straight slap a dick in it"!!