blue moon


Definition of blue moon

1 : a very long period of time usually used in the phrase once in a blue moon such people happen along only once in a blue moonSaturday Rev.
2 : a second full moon in a calendar month

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Synonyms for blue moon


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Examples of blue moon in a Sentence

once in a blue moon we'll get dressed up and eat in a fancy restaurant
Recent Examples on the Web But every once in a blue moon, a new trick will appear out of nowhere and blow me away. Yoni Heisler, BGR, "Apple fans are obsessed with this TikToker’s awesome iPhone hack," 24 Feb. 2021 The next time there will be a blue moon on Halloween will be in the years 2039, 2058, 2077 and 2096. David Petkiewicz, cleveland, "Spectacular blue moon rises over Cleveland on Halloween night (photos)," 1 Nov. 2020 Not only is Saturday Halloween, but there will also be a blue moon. Sarah Midkiff,, "According To TikTok, John Mulaney Started The Pandemic — But He’s Also Going To End It," 30 Oct. 2020 But in the odd season with four full moons, the third was considered the blue moon. Theresa Machemer, Smithsonian Magazine, "This Halloween, Look for the Hunter’s Blue Moon," 26 Oct. 2020 Halloween night in Austin was beautiful, graced with a blue moon. Lawrence Wright, The New Yorker, "The Plague Year," 28 Dec. 2020 This year the blue moon will come in the last third of summer. oregonlive, "Stargazing calendar 2021: Eclipses, meteor showers and other astronomical events this year," 30 Dec. 2020 According to the first, more common definition, the last blue moon was in March 2018, according to Chris Ciaccia, Fox News, "Blue moon to appear on Halloween for the first time in nearly 20 years," 30 Oct. 2020 Finally, Blue Star is celebrating Halloween’s blue moon with a preview of her new restaurant-lounge-theater venue, Häos on Church. Matthew J. Palm,, "Orlando shows: Last-minute Halloween thrills," 29 Oct. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'blue moon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of blue moon

1821, in the meaning defined at sense 1

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Time Traveler for blue moon

Time Traveler

The first known use of blue moon was in 1821

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Statistics for blue moon

Last Updated

1 Mar 2021

Cite this Entry

“Blue moon.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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