· acting or moving or capable of acting or moving quickly; "fast film"; "on the fast track in school"; "set a fast pace"; "a fast car"

Antonym(s): slow

· (used of timepieces) indicating a time ahead of or later than the correct time; "my watch is fast"

Antonym(s): slow

· at a rapid tempo; "the band played a fast fox trot"

Antonym(s): slow

· (of surfaces) conducive to rapid speeds; "a fast road"; "grass courts are faster than clay"

· resistant to destruction or fading; "fast colors"

· unrestrained by convention or morality; "Congreve draws a debauched aristocratic society"; "deplorably dissipated and degraded"; "riotous living"; "fast women"

Synonym(s): debauched, degenerate, degraded, dissipated, dissolute, libertine, profligate, riotous

· hurried and brief; "paid a flying visit"; "took a flying glance at the book"; "a quick inspection"; "a fast visit"

Synonym(s): flying, quick

· securely fixed in place; "the post was still firm after being hit by the car"

Synonym(s): firm, immobile

· unwavering in devotion to friend or vow or cause; "a firm ally"; "loyal supporters"; "the true-hearted soldier...of Tippecanoe"- Campaign song for William Henry Harrison; "fast friends"

Synonym(s): firm, loyal, truehearted

· (of a photographic lens or emulsion) causing a shortening of exposure time; "a fast lens"

· most quickly

Synonym(s): quickest