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fast asleep

fast asleep adjective: synonym of sound asleep.

Adjective

fast asleep (not comparable)

  1. (idiomatic) Synonym of sound asleep.
    Synonyms:
    sound asleep

fast asleep meaning in Sanskrit

fast asleep in Sanskrit

fast asleep, in a deep sleep
सुषुप्त súṣupta

Synonyms of fast asleep

Origin of fast asleep

The original sense of fast in this term is the "firmly gripped or anchored" sense, thus as if stuck fast (embedded firmly) in sleep, but the homonymy with fast as in "quickly" happens to dovetail with the fact that a very tired person will archetypally fall asleep quickly, which tends to color this term with a connotation of falling asleep both quickly and deeply.

Questions about fast asleep

What does fast asleep mean?
Fast asleep means synonym of sound asleep.
What is fast asleep in Sanskrit?
Fast asleep in Sanskrit is सुषुप्त (súṣupta). See Fast asleep meaning in Sanskrit.
What part of speech is fast asleep?
Fast asleep is an adjective.

Words near fast asleep in the dictionary

  1. Fassnachts
  2. fast
  3. fast and furious
  4. fast and loose
  5. fast as lightning
  6. fast asleep
  7. fast backward
  8. fast backwarded
  9. fast backwarding
  10. fast backwards
  11. fast blue optical transient

Source and license

Adapted from Wiktionary: fast asleep (page history and authors); सुषुप्त (Sanskrit) (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: en-au-fast asleep.ogg.

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