ZM is another name for a male "slumber party". It involves staying at ones house and staying up watching movies and playing video games. Originates from the word Zombie-marijuanathon. It involves smoking weed while playing call of duty.
"Dude! ZM at my house tomorrow"
by Poonmarijuana May 30, 2016
1. Not ZIMA 2. Not Zowel Movement 4. there is no 3 5. Don't try to !urban me!
I tried to !urban ZM and I failed. I fail at life :(.
by Alfred Stoner February 16, 2005