- (US) Initialism of General Services Administration.
- (aviation, travel) General Sales Agreement. A contact between an airline and a travel company to provide customer service in a region where the airline does not have an office.
- (incest) genetic sexual attraction
GSA (plural GSAs)
- General Sales Agent. The travel company having such an agreement.
- gay-straight alliance: a student-run society for discussion of issues relating to sexual orientation