Taken from the times miners had a Canary down in the mine shafts to detect deadly gasses, this is a check of a toilet after destroying it with your bodily waste to make sure it's clear.
by Sir_Rutto September 10, 2019

A function check is a military euphemism for male masturbation, as if to compare the penis to a weapon.
Private Duffy, perform a function check on that M4 rifle.
Yo man, I’m so horny I’m going to go perform a “function check”. If you know what I mean.
Yo man, I’m so horny I’m going to go perform a “function check”. If you know what I mean.
by Humpty1963 December 8, 2022

Where a gal promises to "pay" you for a favor by spreading her legs for you afterwards, but then unexpectedly insists that you wear a condom, which of course drastically reduces the pleasure of the act and thus largely negates any true value of said "payment".
Any time that a "willing" chick offers me sex in exchange for my assistance, I always make sure to first ask her if she's gonna let me "do it bareback" before I decide whether or not to bust my ass for her --- oh, I might still help her out even if she wants me to use protection, of course, but I still like to know what I'll be actually getting out of da deal --- I've gotten too many rubber checks in da past!
by QuacksO September 9, 2018

by fuheiu August 2, 2023

by BoodyODabloons June 12, 2023

Juicy-er than fried chicken
Hey how about I tell you about My Fat Ugly Gross Disgusting Despicable Delectable Suckulent Fuckulent juicy tender balls that smoother cares your check as the hairs do a little tickle you fuck
by PandaJizz42 November 3, 2023

When another man points out a piece of food and/or thick sauce on another mans face. Usually around the lips.
Alex walks in with a bit of ranch on his lips
Bill, "Sperm Check."
*Alex quickly wipes ranch from lips*
Bill, "Sperm Check."
*Alex quickly wipes ranch from lips*
by tittysprinklers December 1, 2013
