keep someone up at night

English

Etymology

(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)

Verb

keep someone up at night (third-person singular simple present keeps one up at night, present participle keeping one up at night, simple past and past participle kept one up at night)

1. (idiomatic, colloquial) to make someone disturbed (such that someone might not sleep well); to be watchful of
   • 2023 March 9, Sauli Niinisto, 9:23 from the start, in Finland's President Sees No Reason to Talk to Putin‎^[1], Bloomberg, archived from the original on 09 March 2023:

     Reporter: You share this border, more than eight hundred miles, with Vladimir Putin. What keeps you up at night?
     Niinisto: Nothing keeps me up at night. But in the daytime we... like I have said, we are not afraid, but we are fully awake.

Further reading

• "keep (one) up at night" in The Free Dictionary (Idioms), Huntingdon Valley, Pa.: Farlex, Inc., 2003–2023.