This is because most fraternities and sororities are named after a series of Greek letters, such as Alpha Delta Pi or Sigma Phi.

VOA: special.2009.09.25

In general,fraternities are for men, while sororities are for women.

VOA: special.2009.09.25

Fraternities and sororities are social organizations for undergraduate college students.

VOA: special.2009.09.25

Fraternity and sororities on campus do have toy drives for mothers like me.

VOA: standard.2009.12.04