n. pl. fra·ter·ni·ties
1. A body of people associated for a common purpose or interest, such as a guild.
2. A group of people joined by similar backgrounds, occupations, interests, or tastes: the fraternity of bird watchers.
3. A social organization at a college or university, traditionally consisting of male students and designated by Greek letters.
4. Roman Catholic Church A sodality.
5. The quality or condition of being brothers; brotherliness.
[Middle English fraternite, from Old French, from Latin frāternitās, from frāternus, fraternal; see FRATERNAL.]
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