half-co-sibling-in-law

Spouse's half-sibling's spouse.

My half-co-sibling-in-law is a good person.

by Wonbig October 13, 2021

Eldest sibling syndrome

Eldest sibling syndrome or E.S.S is When you are the eldest amongst your siblings so you automatically fall into the cycle of having to use things until they are disintegrating because you can't ask for new ones.

Whereas on the other hand any younger sibling can ask for whatever and get it instantaneously because they are not the eldest.

Examples of this include tattered clothes and using things until they break.

Person 1: Dude. Your underwear is literally hanging by the elastics. Why don't you get new ones?

Person 2: Oh you know why. Ask my little brother.

Person 1: No wait. Don't tell me you have Eldest Sibling Syndrome!?
Person 2: It's gotten worse

by Mad King JJ July 29, 2017

Oil Siblings

Special bond between a guy and a girl created after both of them have had, alternatively or simultaneously, sexual intercourse with the same girl.

-Hey, Monica, guess who I tapped last night!

-Who?
-Jessica!
-No way, I did her last month. We're oil siblings!

by Oyster Lover February 1, 2016

Younger Sibling Syndrome

When a younger sibling constantly feels inferior to their older sibling.

there always compared to their sibling, it’s a clear case of Younger Sibling Syndrome

by Imhotandurnot November 14, 2022

Sibling

You’d give them a kidney but wouldn’t allow them to borrow your charger

Omg I hate my sibling they always steal my shit!

by Emmyj September 24, 2021

Siblings

The little shits that likes to fuck up my life and screw me over. :)

Bro my little shit sucked the other little shits cock last night. (Siblings)

by @SmexyPeen October 19, 2020

Liquid sibling

A sibling of darkness.

Your liquid sibling is trying to scare everybody again. He/she is too chicken shit to say/do some of that shit in real life, but will show up in a video game as a video game character trying to fight you.

by Solid Mantis October 7, 2020