sisterm 

A special kind of sister. You like this type of sister and feel close to her only because you feel obligated.

Older Sister: I probably wouldn't like you if you weren't my sisters. So you are my sisterm.

Younger Sister: Oh....

sisterm by thebestsister123 June 21, 2011

Plump Sister 

A woman who has put on a few pounds since the last time that a random 72 year old Uncle will say to Larry, the cousin twice removed, this kind of thing:

Uncle: "Golly! That's Suzanne? She has gotten to be a real Plump Sister since the last time I saw her."
Larry: "Must've been back in the Seventies. Before the kid. Kids. Who knows."

Uncle: "It was May 1979. When they got married...wow she just blimped out!" Larry: "Total butterball. Plump Sister, shame."

Plump Sister by MissPriss9 January 12, 2019

Sister X 

The sister with the most not-relative-siblings in Vietnam.

- Do you know sister X?
- Of course, she's the one with the most siblings in Vietnam.

Sister X by Bé Iu Của Chị X April 23, 2021

Big Sisters & Big Brothers 

Organizations that pair young kids with older "brothers" & "sisters". They spend quality time together & it makes up for not having a Mom or Dad. Great for youngsters!

{Big Sisters & Big Brothers] are in practically every town & city nationwide.

Big Sisters & Big Brothers by Starchylde May 21, 2016

Time To Chuck My Muck Over Your Sister's Jubblies 

A politer way of saying to a friend, i'm going to fuck your sister then sloppy jizz over her tits

Dave: Bobby, since you wouldn't make me a brew its Time To Chuck My Muck Over Your Sister's Jubblies

Time To Chuck My Muck Over Your Sister's Jubblies by Greg_the_Smeg February 7, 2019

The Diary of Princess Pushy’s Sister 

The supposedly long awaited (and self published) memoire of Samantha Markle wherein she promised to ‘spill the tea’ on Meghan Markle, The Duchess of Sussex, but as usual failed to deliver.

Wow The Diary of Princess Pushy’s Sister was so bad Sam couldn’t give it away for free!

The Diary of Princess Pushy’s Sister by Blood Sister October 6, 2023

sister zoned 

When a guy/ girl you like says "you are like my sister" or "you are like the little sister I've never had" or "I love you like a sis" It is worse than being friend zoned, it's all the way past friends to family. You probably have a 2% chance of getting out of the sister zone and having a relationship with that person.

I thought we were on a date, but he sister zoned me twice. I guess we were just hanging out.

sister zoned by Queen B, Bitch! June 5, 2015