blue moon
Học thuậtThân thiện
Definition
- Noun:
- A very long period of time; an indefinite, extended duration. This meaning is primarily used in the idiomatic phrase "once in a blue moon."
- A rare or unusual event. Refers to something that occurs very infrequently.
Usage
The term "blue moon" is almost exclusively used in the fixed idiomatic expression "once in a blue moon." This phrase functions as an adverbial phrase to describe the extreme rarity of an event.
Examples
- Noun (in idiom):
- My sister lives abroad, so I only see her once in a blue moon.
- He's very careful with his money and eats at a restaurant only once in a blue moon.
- Such a total eclipse of the sun happens only once in a blue moon.
Advanced Usage
- "a blue moon": Can be used poetically or figuratively to mean a very rare occurrence, though this is less common than the full idiom.
- Opportunities like this come along only a blue moon.
Variants and Related Words
- Blue moon: In modern astronomy, a "blue moon" can refer to the second full moon in a single calendar month, which is the origin of the idiom's meaning of rarity. This is a separate, technical definition.
- Rarity (n): The state or quality of being rare.
- Infrequency (n): The state of not happening often.
Synonyms
- Rarely
- Seldom
- Hardly ever
- Infrequently
Related Idioms
- Once in a blue moon: Very rarely; almost never.
- He visits his hometown once in a blue moon.
- Every blue moon: An occasional variant with the same meaning as "once in a blue moon."
- We get a chance to relax like this every blue moon.
Noun
- a long time
- something that happens once in blue moon almost never happens