blue moon

noun

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

Synonyms

aeon (or eon), age, coon's age, cycle, donkey's years [chiefly British], eternity, forever, long, months, 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

The green clovers, pink hearts, blue moons and yellow stars are infused with vanilla flavoring and plenty of sugar. Hannah Chubb, PEOPLE.com, "You Can Now Buy Bags of Oversized Lucky Charms Marshmallows Because Dreams Do Come True," 9 Aug. 2019 For most, dinner at Pernoi will be a once in a blue moon splurge, saved for milestone anniversaries and the most special occasions. Mark Kurlyandchik, Detroit Free Press, "An early taste of Pernoi, one of metro Detroit's most anticipated restaurants ever," 19 June 2019 Over the last 15 years he's created whimsical scenes including a blue moon, a sparkling sea of CDs, and even lollipops of light. CBS News, "American Wonders: California's glowing "Field of Light"," 23 July 2019 Just two people who rarely have time to see each other, who aren’t quite right for each other, who enjoy each other’s company every once in a blue moon. Natalie B. Compton, latimes.com, "A romance that began on a plane didn’t survive the landing," 22 June 2019 The most recent astronomical blue moon occurred in May 2016. Daisy Hernandez, Popular Mechanics, "Here's What You Need to Know About Tonight's Blue Flower Moon," 17 May 2019 For the first time in more than 150 years in the U.S., a total lunar eclipse coincided with a blue moon and supermoon. Ashley May, USA TODAY, "Incredible images of the rare blue blood moon," 31 Jan. 2018 This is also the second month in 2018 with a blue moon. Leigh Morgan, AL.com, "Blue moon 2018: Second -- and last -- blue moon of year rises tonight," 1 Dec. 2017 The unicorn will join seven other marshmallow shapes: hearts, stars, horseshoes, clovers, blue moons, rainbows, red balloons. Brett Molina, USA TODAY, "Lucky Charms is retiring one of its marshmallows to add a unicorn," 20 Feb. 2018

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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