#1 brother n. [blood brother] a male with the same parents as someone else; "my brother still lives with our parents". wn
#2 brother n. a male person who is a fellow member (of a fraternity or religion or other group); "none of his brothers would betray him". wn
#3 brother n. [buddy, chum, crony, pal, sidekick] a close friend who accompanies his buddies in their activities. wn
#4 brother n. [comrade] used as a term of address for those male persons engaged in the same movement; "Greetings, comrade!". wn
#5 brother n. [Brother] (Roman Catholic Church) a title given to a monk and used as form of address; "a Benedictine Brother". wn
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