be up all night — to stay awake and not sleep during the entire night, usually because of work, study, worry, or entertainment
Part of speech: VERB
Definition: to stay awake and not sleep during the entire night, usually because of work, study, worry, or entertainment
Pronunciation (IPA): /bi ʌp ɔːl naɪt/
Example Sentences
- I was up all night because my cat kept meowing at the door like a tiny alarm clock.
- He was up all night reviewing grammar rules for the CSAT English exam.
- We were up all night binge-watching a drama, and now we both look like zombies.
be up all night
VERB[/bi ʌp ɔːl naɪt/]
to stay awake and not sleep during the entire night, usually because of work, study, worry, or entertainment

He had to be up all night finishing the project before Monday's deadline.
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🎤Pronunciation
🌳Etymology
Origin
This phrase derives from spatial metaphors fundamental to English, where 'up' conventionally represents wakefulness and consciousness, while 'down' represents sleep. The expression combines the verb 'be' with the adverbial particle 'up' (meaning awake or out of bed) and the temporal phrase 'all night' to create an idiom denoting continuous wakefulness throughout the night.
Breakdown
be (auxiliary verb indicating state) + up (adverbial particle meaning awake/vertical position, figuratively alert) + all (totality) + night (temporal noun). The spatial metaphor 'up' = awake originates from the physical association of standing/sitting upright with wakefulness.
🎵Rhyme
🔗Collocations
📝Examples
“I was up all night because my cat kept meowing at the door like a tiny alarm clock.”
“He was up all night reviewing grammar rules for the CSAT English exam.”
“We were up all night binge-watching a drama, and now we both look like zombies.”
“The new parents were up all night taking turns comforting the crying baby.”
📚Related Words
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