What is yes'm?

This is a short form of 'Yes ma'am'. When used to a guy, it is a slight and unnoticed insult. Very good for an annoying boss.

Your mother: "Get your ass working now!"
You: "Yes'm."

Your boss: "Get your ass working now!"
You: ( snickering ) "Yes'm."

yes'm - meme gif

A shortened version of yes ma'am, much like yessum, though it's even shorter than that. Used by them lazy folk who dang can nay type no good.

I want you to fry the vegetables, clean the pantry, and shave your god damn balls.
Yes'm.