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blue moon

noun

Definition of blue moon

  1. 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 moon — Saturday Rev.

  2. 2 :  a second full moon in a calendar month

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Examples of blue moon in a Sentence

  1. once in a blue moon we'll get dressed up and eat in a fancy restaurant

First Known Use of blue moon

1821

blue moon Synonyms

Synonyms
aeon (or eon), age, coon's age, cycle, donkey's years [chiefly British], eternity, forever, long, months, moon
Related Words
infinity; lifetime
Near Antonyms
flash, instant, jiffy, minute, moment, second, shake, split second, trice, twinkle, twinkling, wink; microsecond, nanosecond

Learn More about blue moon

  1. See words that rhyme with blue moon Thesaurus: All synonyms and antonyms for blue moon

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blue moon

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Examples: blue moon in a Sentence