OMSM 

on my step momma- when ur step mom is more involved in yo life, use omsm

“we boutta square up OMSM”

OMSM by nat.stole.yo.bih July 6, 2021

OMSMN 

oh my shizzle my nizzle

INVENTED BY RILEY.

on msn;

'he's like, more famous than the other guy'
'OMSMN'

OMSMN by hayleytompope October 21, 2008

omsmg 

stands for Oh my sarah michelle gellar. derived from "omg" but substituting god with sarah michelle gellar. a very controversial comparison.

omsmg! that shirt is soooo cool!!

omsmg by Spike_2009 December 15, 2009