stepbrat 

A child (of any age) from your spouse's former marriage who treats you like shit because they can.

Also one who manipulates their divorced father via his guilt. This manipulation can be to get him to buy them things, or to get daddy yelling on step -mom

The stepbrat is relentless in his victim hood, telling lies to make dad's wife look bad.

The stepbrat spewed her foul psychotic one-liners at me while her father just stood there, watching.

stepbrat by OverIt December 3, 2013

Stepbrother 

Someone who has to pull his stepsister out a washing machine

STEPSISTER STOP GETTING STUCK IN WASHING MACHINES! stepbrother screams

Stepbrother by Iwillkillmyselfwithpeanuts September 9, 2020

Stepbrother 

Friend to have sword fights with

I beat my stepbrother in a sword fight yesterday

Stepbrother by Rectum rocker May 15, 2009

Stepbrothering

To rub your scrotum on something, as seen by the scene in the movie "Stepbrothers" starring Will Ferrell and John C. Reily, where Will Ferrell's character rubs his ballsack on John's drumset.

Simaliar to teabagging.

I just STEPBROTHERED your face.

Pfft. Only noobs stepbrother after a double kill.

I just was caught Stepbrothering.

Stepbrothering by Ol' Betsey April 21, 2009

stepbrother-in-law 

1- Stepsibling's husband.
2- Spouse's stepbrother.

My stepbrother-in-law is a good person.

stepbrother-in-law by Wonbig October 13, 2021

eskimo stepbrothers 

when one man fingers a chick that another man has had sex with, then the two men are eskimo stepbrothers. similar to eskimo brothers

Rick fingered a chick last night and later found out that his friend James had banged her a month ago. Rick and James are now eskimo stepbrothers.

eskimo stepbrothers by skirtripperclubprez September 6, 2011

Stepbrother-In-Law 

The title given to someones brother of sisters boyfriend if they're not married

Juan: Who's this Harry geezer?
Tom: Oh he's my sisters boyfriend, that makes him my stepbrother-in-law
Juan: Surely he's your stepbrother?
Tom: Nah fam, he's not married to my sister

Stepbrother-In-Law by why_am_1_doing_this May 1, 2019