STM 

Acronym for "spanking the monkey".

I gotta go on cam to STM before the wife gets back.

STM by livva_nyc February 27, 2009

STM 

One who pretends to be good at a particular sport, but in reality cannot play it whatsoever. Can be used in a sentence with yayaya with severe sarcasm.
Also can be used as an insult term in basketball to an opposing player on the court who cannot play according to regulation(s).

"Yayaya! Way to shoot that airball, you're not STM."

or

"I enjoy the way you got blocked at today's game. Continue with your STM-ness and you'll be an all-star soon!"

STM by Thomas December 3, 2003

STM 

Short Tempered Midget

STMD: Short Tempered Midget Disease

Me: Bruh Margaret got so mad at me yesterday, too bad she can't do shit since she's like 5'1
Friend: Yea she's diagnosed with STMD. I hate people with STM.

STM by Sadoilem January 23, 2017

STM 

STM means skinny to muscle. The creator can be found on stm__fitness Instagram

Wow you’re making gains

Yeah I’m STM now. As I’ve been following the program which is on stmfitness.bigcartel.com

STM by STM Fitness December 1, 2018

STM 

STM: Shut their mouths.

It’s none of their business to talk about my life; ask them to STM

STM by crazy cuckoos October 27, 2020

stm 

Should Talk More

Snapchat
Crush : we stm
You: yeah

stm by Issy😴 January 20, 2021

STM 

sent to most

someone talk
stm

STM by anonymous November 2, 2021