blue moon


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blue moon

n.
1.
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.]

blue moon

n
1. the second full moon occurring within a calendar month
2. once in a blue moon informal very rarely; almost never
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.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).
References in classic literature ?
Monsieur said he didn't, except once in a blue moon.
Think the moon is a blue moon, a single elephantine sapphire.
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.
Caption: Tide chart reveals two full moons in March, as in January, a "double blue moon," not seen since spring of '99.
Then add on a total lunar eclipse and while the moon is in the Earth's shadow it became a reddish color making it a "blood moon" hence super blue moon blood moon.
It was the first Blue Moon - the second full moon in a calendar month - since July 2015 .
A lunar eclipse, supermoon and a blue moon all coincided for the first time since March 31, 1866.
It's the first time in 35 years a blue moon has synced up with a supermoon and a total lunar eclipse, the latter also called a blood moon because of its red hue.
A blue moon, meanwhile, does not refer to hue, but refers to the second full moon of the calendar month.
A blue moon, defined as the second full moon in a calendar month, was due to rise in the sky yesterday evening for the first time since July 2015.
A supermoon occurs when the full moon is closest to the earth, while a blue moon refers to the second full moon of the month - a rare occurrence - which reportedly happens once in every two years and eight months.
A blue moon is when a second full moon occurs in a calendar month.