(Roman Catholic Church) a title given to a monk and used as form of address(noun.person)
Example: A Benedictine Brother.
source: wordnet30
A male person who has the same father and mother with another person, or who has one of them only. In the latter case he is more definitely called a half brother, or brother of the half blood.(noun)
source: webster1913
verb (v)
To make a brother of; to call or treat as a brother; to admit to a brotherhood.(verb)