: 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

Examples of four-o'clock in a Sentence

Recent Examples on the Web Annuals—like kochia, four-o'clock, strawflower, impatiens, moonflower, and angel's-trumpet—and perennials—like peony, bee balm, and hosta—can substitute for shrubs the first year or two. Viveka Neveln, Better Homes & Gardens, 20 Feb. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'four-o'clock.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1756, in the meaning defined above

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

Dictionary Entries Near four-o'clock

Cite this Entry

“Four-o'clock.” Dictionary, Merriam-Webster, Accessed 21 Feb. 2024.

Kids Definition


: an American garden plant with fragrant yellow, red, or white flowers that open late in the afternoon

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