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

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 Esposito’s Genny Savastano wasn’t born under a bad sign, with a blue moon in his eyes. Andy Meek, BGR, 2 Mar. 2022 And once in a blue moon, a fabulous one comes up for sale: such is the case with the Lanier House, a Beaux-Arts gem on East 35th Street. Leena Kim, Town & Country, 28 Apr. 2022 The rarer, blue moon’s light passes through larger dust particles. Manasee Wagh, Popular Mechanics, 14 Apr. 2022 Edinson Cavani, the current second-string centre forward who does pose a threat on the pitch, can only play once in a blue moon and spends the rest of the time on the sidelines or in the treatment room. Liam Canning, Forbes, 17 Apr. 2022 As for giving up goals, well, that happens once in a blue moon. Matt Le Cren,, 12 Apr. 2022 The next blue moon is forecasted for August 2023, much sooner than the 19 years one Facebook post claimed. Miriam Fauzia, USA TODAY, 28 Oct. 2021 Sometimes a blue moon can fall on Halloween, as the post indicates. Miriam Fauzia, USA TODAY, 28 Oct. 2021 The last blue moon to appear happened in October of 2020 — and on the night of Halloween. Karly Williams, Chron, 19 Aug. 2021 See More

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.

First Known Use of blue moon

1821, in the meaning defined at sense 1

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Time Traveler for blue moon

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The first known use of blue moon was in 1821

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Dictionary Entries Near blue moon

blue monkey

blue moon

blue morpho

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Statistics for blue moon

Last Updated

5 Jun 2022

Cite this Entry

“Blue moon.” Dictionary, Merriam-Webster, Accessed 27 Jun. 2022.

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