Definitions of brother:
- noun: a male with the same parents as someone else
Example: "My brother still lives with our parents"
- noun: (Roman Catholic Church) a title given to a monk and used as form of address
Example: "A Benedictine Brother"
- noun: a male person who is a fellow member (of a fraternity or religion of other group)
Example: "None of his brothers would betray him"
- noun: used as a term of address for those male persons engaged in the same movement
- noun: a close friend who accompanies his buddies in their activities