a local or national organization of male students, primarily for social purposes, usually with secret initiation and rites and a name composed of two or three Greek letters.

a group of persons associated by or as if by ties of brotherhood.

any group or class of persons having common purposes, interests, etc.

the medical fraternity.

an organization of laymen for religious or charitable purposes; sodality.

the quality of being brotherly; brotherhood

liberty, equality, and fraternity.

the relation of a brother or between brothers.

noun

sisterhood , sorority

noun

affiliation , camaraderie , club , fellowship , frat , guild , house , kinship , order , sisterhood , society , sorority , association , confederation , congress , federation , league , organization , brotherhood , brotherliness , circle , union