[fra.ter.ni.ty] n, pl -ties (14c) 1: a group of people associated or formally organized for a common purpose, interest, or pleasure: as a: a fraternal order b: guild c: a men's student organization formed chiefly for social purposes having secret rites and a name consisting of Greek letters d: a student organization for scholastic, professional, or extracurricular activities "a debating ~"
2: the quality or state of being brothers: brotherliness
3: persons of the same class, profession, character, or tastes "the racetrack ~"