Like a bromance and a sismance but with a boy and a girl that have a awesome relationship but not in the relationship way.
Person 1 : WHOA did you see Bob and Becky?
Person 2: I KNOW!! They wont stop hanging out they totally have a brosismance.
Person 2: I KNOW!! They wont stop hanging out they totally have a brosismance.
by CEMPH April 24, 2011
Get the brosismancemug.