Open English Wordnet
Nouns
(n)brother, blood brothera male with the same parents as someone else“my brother still lives with our parents” (n)brothera male person who is a fellow member (of a fraternity or religion or other group)“none of his brothers would betray him” (n)brother, comradeused as a term of address for those male persons engaged in the same movement“Greetings, comrade!”