Initialism of science fiction or speculative fiction, often used to avoid having to choose between the two. / Initialism of square feet. / Initialism of spontaneous fission.

Initialism of San Francisco. / (Ireland, UK politics) Initialism of Sinn Féin; an Irish political party. / (video games) Initialism of Street Fighter. / (motor racing) Initialism of Super Formula.

(in personal ads) Initialism of smoker-friendly: not objecting to people who smoke tobacco

(dated) Alternative form of SF (science fiction) / Abbreviation of significant figure(s).

a book size one sixty-fourth of the size of a standard uncut sheet of paper (less 7.5 cm (3") in height)

plural of Sf

Alternative form of ATSF

plural of SF

Alternative form of SF&F

A genre of fiction, combining the subgenres of science fiction (or speculative fiction) and fantasy.