ENGLISH
REFERENCE

sleepless

adj.
B2 Upper Intermediate US //ˈsɫipɫəs// UK //slˈiːpləs// sleep·less

adj. unable to sleep or happening during a time when you cannot sleep. You use this to describe a night when you stay awake or a person who is very tired.

adj. characterised by a lack of sleep; unable to rest or find slumber. Often used to describe a period of time or the state of a person.


SIMPLE

She spent a sleepless night worrying about her exam.

CONTEXTUAL

After three sleepless nights with the newborn, the parents were struggling to stay focused during the day.

COMPLEX

The protagonist's sleepless vigil by the window serves as a recurring motif, highlighting his growing anxiety and inability to find peace in his new surroundings.

Synonyms
Origin

From Middle English slepeles, from Old English slǣplēas; equivalent to sleep + -less.

Usage

Commonly used both attributively before a noun and predicatively after linking verbs like 'remain' or 'be'.

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