Significant Brother 

What two bros in a bromance call eachother. Not to be confused with a homosexual relationship, using this term signifies a strong friendship between two completely straight males. Significant brothers have love for eachother but are not in love with eachother.

Girl: Are you gay?
Bro: Nah, I just have a significant brother.

Some Kid: Do you know Sean?
Some Bro: Know him? Bro, He's my significant brother!

Significant Brother by BigMac12 September 10, 2010

Significant Brother 

A committed partner in a long-term bromance.

Dirk: Hey, you wanna go to the bar tonight?

Lewis: Maybe but I'll have to check with my significant brother first.

Significant Brother by mommysdirtypillows October 19, 2009

Significant brother 

A man married to his sibling/step-sibling.

Pam: did you hear Brittany got married? I wonder who the groom is...
Karen: oh, she married her step brother. Such a good love story, when one finds romance with their significant brother.

(Cue banjos)

Significant brother by BabsCatfish August 2, 2019

Brothers before significant others 

Bros before Hoes

Guy 1: Hey I'm about to watch this new episode of skins, is that ok?

Guy 2: Wtf I told you I wanted to watch that

Guy 1: But I really like this girl, and itd be a great new discussion area for us

Guy 2: Fuck you man, brothers before significant others

Brothers before significant others by Adamkos101 December 2, 2011