Fast asleep
Fast asleep adjective - Sleeping deeply.
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Synonyms for Fast asleep
Fast and fast asleep are semantically related. In some cases you can use "Fast" instead an adjective phrase "Fast asleep".
Fast
Fast adjective - Moving, proceeding, or acting with great speed.
Fast asleep and fast are semantically related. Sometimes you can use "Fast asleep" instead an adjective "Fast".
Mutual synonyms
Cite this Source
Fast and Fast asleep. (2016). Retrieved 2026, August 02, from https://thesaurus.plus/related/fast_asleep/fast
Fast asleep & Fast. N.p., 2016. Web. 02 Aug. 2026. <https://thesaurus.plus/related/fast_asleep/fast>.
Fast or Fast asleep. 2016. Accessed August 02, 2026. https://thesaurus.plus/related/fast_asleep/fast.
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