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REFERENCE

fast

adj. · adv. · v. · n.
US //ˈfæst// UK //fˈɑːst// fast
  1. 1 quick or rapid (adj.)
    A1 Beginner

    moving or happening at high speed.

    characterised by high speed; capable of rapid movement or action.

    Example

    The fast train to London takes less than two hours.

    Example

    The company's fast growth surprised many investors who had expected a much slower entry into the European market.
  2. 2 ahead of time (adj.)
    B1 Intermediate

    showing a time that is later than the real time.

    indicating a time ahead of the actual or correct time, typically in reference to a clock or watch.

    Example

    My watch is five minutes fast, so I always arrive early for meetings.

    Example

    He intentionally kept his alarm clock ten minutes fast to ensure he never missed the early morning commute.
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  1. 3 firmly fixed (adj.)
    B2 Upper Intermediate

    attached firmly so that it cannot move.

    firmly fixed or attached; secure against movement or displacement.

    Example

    Make sure the knot is fast before you start climbing.

    Example

    The tradition remains fast in the rural provinces, despite the rapid modernisation occurring in the capital city.
  2. 4 quickly (adv.)
    A1 Beginner

    at high speed.

    at a high rate of speed; rapidly.

    Example

    You are driving too fast for this narrow road.

    Example

    The news spread fast across the small town, reaching almost every household before the official announcement was made.
    Pitfall
    He ran very fastly to catch the bus.
    He ran very fast to catch the bus.

    The word 'fast' is both an adjective and an adverb; 'fastly' is not a word in modern English.

  3. 5 deeply asleep (adv.)
    B1 Intermediate

    completely or deeply, usually used with the word 'asleep'.

    completely or soundly; almost exclusively used in the collocation 'fast asleep'.

    Example

    The baby was fast asleep in her cot after the long walk.

    Example

    Exhausted by the day's hike, the travellers were fast asleep long before the storm began to rattle the cabin windows.
  4. 6 to abstain from food (v.)
    B2 Upper Intermediate Medicine

    to eat little or no food for a period of time, often for religious or medical reasons.

    to abstain from all or some kinds of food or drink, especially as a religious observance or for medical purposes.

    Example

    Patients must fast for twelve hours before having the blood test.

    Example

    Many cultures require followers to fast during specific holy months to demonstrate spiritual discipline and empathy for the poor.
  5. 7 period of not eating (n.)
    B2 Upper Intermediate Religion

    a period of time when you do not eat food.

    an act or period of fasting.

    Example

    He broke his three-day fast with a small bowl of soup.

    Example

    The community gathered for a large celebration to mark the end of the traditional religious fast.
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