\ ˈfȯr-ə-ˌkläk How to pronounce four-o'clock (audio) \

Definition of four-o'clock

: any of a genus (Mirabilis) of chiefly American annual or perennial herbs (family Nyctaginaceae, the four-o'clock family) having apetalous flowers with a showy involucre simulating a calyx especially : a garden plant (M. jalapa) with fragrant yellow, red, or white flowers opening late in the afternoon

First Known Use of four-o'clock

1756, in the meaning defined above

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The first known use of four-o'clock was in 1756

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Dictionary Entries Near four-o'clock

Four Noble Truths


four-o'clock family

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Cite this Entry

“Four-o'clock.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2022.

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