Blue moon
Blue moon noun - A long or seemingly long period of time.
Usage example: once in a blue moon we'll get dressed up and eat in a fancy restaurant
Cite this Source
Moon and Blue moon. (2016). Retrieved 2026, August 02, from https://thesaurus.plus/related/blue_moon/moon
Blue moon & Moon. N.p., 2016. Web. 02 Aug. 2026. <https://thesaurus.plus/related/blue_moon/moon>.
Moon or Blue moon. 2016. Accessed August 02, 2026. https://thesaurus.plus/related/blue_moon/moon.
Google Ngram Viewer shows how "blue moon" and "moon" have occurred on timeline