1 definition by brofessor of the brolanguage.

when bros do things together. (two-some, three-some.)

note: has to be bros, not bro.

not to be confused with bra(brow)wesome.(meaning awesome in english.)

when 2 bros share a bed in a none bromosexual way. It is a Brosome
or

when 2 bros embrace each other w/a bro-hug...it is a bromantic brosome broment.

When bros have a bro-twurst together. They are doing so as a brosome.

conclusion: when bros do bromal stuff together, they do so as a brosome.
Get the Brosome mug.