fast - noun

abstaining from food

fast - verb

• abstain from certain foods, as for religious or medical reasons
• abstain from eating

fast - adjective

• acting or moving or capable of acting or moving quickly
• (used of timepieces) indicating a time ahead of or later than the correct time
• at a rapid tempo
• (of surfaces) conducive to rapid speeds
• resistant to destruction or fading
• unrestrained by convention or morality
• hurried and brief
• securely fixed in place
• unwavering in devotion to friend or vow or cause
• (of a photographic lens or emulsion) causing a shortening of exposure time

fast - adverb

• quickly or rapidly (often used as a combining form)
• firmly or closely

fast - thesaurus

debauched   degenerate   degraded   dissipated   dissolute   fasting   firm   flying   immobile   libertine   loyal   profligate   quick   riotous   tight   truehearted