Noun:
1: fast, fasting abstaining from food
Verb:
1: fast abstain from certain foods, as for religious or medical reasons; "Catholics sometimes fast during Lent"
2: fast abstain from eating; "Before the medical exam, you must fast"
Adjective:
1: blistering, fleet, accelerated, alacritous, speedy, immediate, accelerating, rapid, winged, speeding, swift, rapid, windy, hurrying, quick, quick, red-hot, fast-breaking, prompt, instant, high-velocity, scurrying, hot, fast, speedy, double-quick, high-speed, instantaneous, straightaway, meteoric, express, fast-paced, smart 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"
2: fast (used of timepieces) indicating a time ahead of or later than the correct time; "my watch is fast"
3: vivace, prestissimo, allegretto, fast, andantino, presto, allegro at a rapid tempo; "the band played a fast fox trot"
4: smooth, fast (of surfaces) conducive to rapid speeds; "a fast road"; "grass courts are faster than clay"
5: barred, fastened, secured, bolted, locked, fast, latched firmly fastened or secured against opening; "windows and doors were all fast"; "a locked closet"; "left the house properly secured"
6: imperviable, impervious, fast resistant to destruction or fading; "fast colors"
7: fast, immoral, dissipated, profligate, dissolute, riotous, libertine, degenerate, debauched, degraded unrestrained by convention or morality; "Congreve draws a debauched aristocratic society"; "deplorably dissipated and degraded"; "riotous living"; "fast women"
8: quick, hurried, fast, flying hurried and brief; "paid a flying visit"; "took a flying glance at the book"; "a quick inspection"; "a fast visit"
9: fixed, firm, immobile, fast securely fixed in place; "the post was still firm after being hit by the car"
10: faithful, loyal, fast, firm, truehearted 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"
Adverb:
1: fast quickly or rapidly (often used as a combining form); "how fast can he get here?"; "ran as fast as he could"; "needs medical help fast"; "fast-running rivers"; "fast-breaking news"; "fast-opening (or fast-closing) shutters"
2: fast, tight firmly or tightly; "held fast to the rope"; "her foot was stuck fast"; "held tight"