Meaning of “asleep” - Learner’s Dictionary

asleep

adjective us uk /əˈsliːp/
be asleep

B1 to be sleeping:

The children are asleep.
I was fast/sound asleep (= sleeping deeply).

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fall asleep

B1 to start sleeping:

He fell asleep in front of the TV.

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(Definition of “asleep” from the Cambridge Learner’s Dictionary © Cambridge University Press)