Definitions
Unable to sleep or passed without sleep.
Word origin
From Middle English slepeles, from Old English slǣplēas; equivalent to sleep + -less.
Used in a sentence
“I spent a sleepless night worrying about the exams.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Up all night”9 letters
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