blue moon

[bloo moon] / ˈblu ˈmun /

NOUN

long period of time

Synonyms

WEAK

ages forever and a day long time years

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Once in a blue moon, a person is willing to do the hard internal work that leads to real, sustainable change.

From Salon • Mar. 21, 2025

Now, celestial enthusiasts can look forward to seeing a super blue moon this week starting Monday.

From Los Angeles Times • Aug. 19, 2024

As blue moons are not that common, it's thought where the phrase "once in a blue moon" comes from.

From BBC • Aug. 19, 2024

Monday’s super blue moon will kick off four consecutive supermoons this year.

From Los Angeles Times • Aug. 19, 2024

Oh, I get it—it’s rare, like once in a blue moon.

From "Booked" by Kwame Alexander