step monster 

A step mother who is vicious and mean.

My step monster wont let me do what I want.

step monster by Sandi68 April 28, 2006

step momster 

A nasty stepmom who always has a resting bitch. Face is unpleasant and treats, her husband and her husband’s family like garbage but her own family can do no wrong.

My step momster got her own kids something lovely for the party but only got my kid a crappy cheap trinket.

step momster by Cat daddy 043 April 9, 2023

stepmonster 

The word used to identify a stepmother that you don't like, get along with, just plain despise. 1st coined in the film St. Elmo's Fire, used chiefly by Demi Moore's character, Jules.

Jules: I have to go. Did the hospital call? Did my stepmonster die?

stepmonster by Tommyt August 25, 2008

stepmonster 

A step mother who is a nightmare to the other children. Known to fight for the mother title in many sinister ways. Pouts when the real mother is in contact with the child or grandchildren. Has no concern about how that looks to anyone..kids, grandkids. A total "one-upper" in every breath

Dammit, my stepmonster Lisa wont leave my mother alone. I mean who do she thinks she is, she has never been and will never be a mother to me

stepmonster by llp1964 April 3, 2009