(of a railway) having a single set of lines so that trains can run only in one direction at a time; single-track / limited to one idea or thought

railroad track, railway track / (topology) A set of curves lying in a surface, meeting one another at their respective endpoints in a specific way that resembles railroad tracks

present participle of fast track

(Australia, Canada, New Zealand, US) Sweatpants.

(rail transport, US) A pair of formed steel rails, separated and supported usually on wooden or concrete ties or sleepers, forming a track along which flange-wheeled railroad vehicles may travel.

(softball, baseball) The dirt or other material on the edge of a baseball or softball field that warns a player that he or she is approaching the fence, especially the portion in the outfield.

(sports, chiefly racing) The lane or track nearest to the interior. / (figuratively) Any advantage.

Used other than figuratively or idiomatically: see track, record.

(music, film) An audio track having the same name as the album, EP or film that it is taken from.

simple past tense and past participle of fast track