The state in which bros are in constant equilibrium through a healthy balance of positive and negative feedback loops.
Bro 1: Hey bro, did I hurt your feelings with the joke I made earlier?
Bro 2: yea bro you did
Bro 1: I am sorry, bro
Bro 2: yea bro its all good, I appreciate your concern for my wellbeing. You are really looking out for me.
Bro 1: you are my bro and I care about you, our bromeostasis is so important to me
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).