brothers
"Brothers" is the plural form of "brother," and it has a few meaningful uses in English — from your actual family to deep bonds of friendship and solidarity. Here are the most common ones.
In religious, political, or social groups, 'brothers' is used to refer to all the male members — or sometimes all members — of that group. It creates a sense of unity and shared purpose. You will often hear this in churches, unions, or movements.
religion / politics / community · Modern, widely used · figurative
In universities, especially in the United States, a fraternity is a social club for male students. The members of a fraternity call each other 'brothers.' It is a formal use of the word within that specific community.
education / university life (especially US) · Modern, widely used