all hours

plural noun

: a very late time
stayed up until all hours

Examples of all hours in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Or picture a science lab, where microscopes can autonomously search for a certain type of molecule—all hours of the day, no humans necessary. — Emily Forlini, Fortune, 27 Aug. 2026 When tallying the total stay of individual detainees, ProPublica counted all hours spent in jail, including weekends and holidays. — Mario Ariza, ProPublica, 27 Aug. 2026 Silvia was pressuring Wyatt to get back together with him, calling at all hours of the night and sitting outside her workplace. — Amanda Lee Myers, USA Today, 18 Aug. 2026 To be the president of the United States is to be on call all hours of the day. — Nicole Kliest, Vogue, 26 July 2026 See All Example Sentences for all hours

Word History

First Known Use

1668, in the meaning defined above

Time Traveler
The first known use of all hours was in 1668

Rhymes for all hours

See All Rhymes for all hours

Browse Nearby Words

all hell breaks loose
all hours
alliable
See all Nearby Words

Cite this Entry

“All hours.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/all%20hours. Accessed 1 Sep. 2026.

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Kids Definition

all hours

plural noun
: a very late time
stayed up until all hours
Last Updated: - Updated example sentences
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