blue moon

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blue moon

a. The third full moon in a three-month calendrical season that has four full moons.

b. The second of two full moons occurring in the same month.

2. Informal A relatively long period of time: I haven't seen you in a blue moon.

[Sense 2, probably from the rare occurrence whereby the moon appears blue from high amounts of dust in the atmosphere, as from a volcanic eruption.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

blue moon

1. the second full moon occurring within a calendar month

2. once in a blue moon informal very rarely; almost never

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

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Noun

blue moon - a long time; "something that happens once in blue moon almost never happens"

colloquialism - a colloquial expression; characteristic of spoken or written communication that seeks to imitate informal speech

long time, years, age - a prolonged period of time; "we've known each other for ages"; "I haven't been there for years and years"

blue moon

noun

Informal. A long time:

eon, eternity, long, year (used in plural).

Informal: age (used in plural).

Idioms: forever and a day, forever and ever, month of Sundays.

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References in classic literature ?

"I go to it only about once in a blue moon. There was an old barrel there, upside down, one side resting on a block of wood.

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Monsieur said he didn't, except once in a blue moon. But when he did?

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Think the moon is a blue moon, a single elephantine sapphire.

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Now and then you might see a rabbit skipping across the road if you were quiet--which, with Anne and Diana, happened about once in a blue moon. Down in the valley the path came out to the main road and then it was just up the spruce hill to the school.

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When recombined in a rocket engine and ignited, both gases will explode, releasing the energy needed to power Blue Moon, the huge lunar lander to be built by Blue Origin.

Rocket Fuel From Water Ice Will Propel Blue Moon Lunar Lander

There are normally only three moons per season, with a blue moon occurring only once every two or three years.

BLUE MOON TREAT FOR STARGAZERS

The Full Blue Moon will appear on the evening of May 18.

Full Blue Moon will appear TONIGHT - what it is and when and where to see it in the UK; It won't actually appear blue, it earns this name due to the fact that it's the third of four full moons in this season

Although named as "Full Flower Blue Moon," it will not actually appear as blue.

'Blue moon' to grace weekend skies

Here's everything you need to know about the Full Blue Moon, including what it is, and how you can see it from the UK.

Full Blue Moon will appear TONIGHT - what it is and how to see it from the UK; Here's everything you need to know about the Full Blue Moon, including what it is, and how you can see it from the UK

According to a news release sent out by Blue Origin, Blue Moon is a "large lunar lander capable of delivering multiple metric tons of payload to the lunar surface based on configuration and mission." The cargo variant, which was revealed yesterday at the announcement, is capable of carrying 3.6 metric tonnes of cargo to the Moon's surface.

BLUE ORIGIN ANNOUNCES BLUE MOON LUNAR LANDER, PROMISES AMERICANS ON MOON BY 2024

Whichever you pick, the chances of winning are still as likely as a blue moon.

Not a lott of hope of me winning mega-millions

Mr Tiger, Betsy and the Blue Moon is the first in what is likely to be a popular series.