How do you use "Once in a blue moon" in a sentence?

I only eat red meat once in a blue moon. He visits once in a blue moon. Once in a blue moon, we get a sunny day in November.

Once in a blue moon

Q: What does "Once in a blue moon" mean?

Very rarely, almost never Something that happens so infrequently it's remarkable when it does occur. A blue moon (second full moon in a calendar month) is genuinely rare, occurring about once every 2.7 years.

Slang Term BritishAmericanAustralian ★★★★★ Very Common Casual

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Meaning: Very rarely, almost never

非常罕见，几乎从不

Muy raramente, casi nunca

めったにない、ほとんどない

아주 드물게, 거의 없다시피

Something that happens so infrequently it's remarkable when it does occur. A blue moon (second full moon in a calendar month) is genuinely rare, occurring about once every 2.7 years.

某件事发生的频率极低，以至于发生时令人惊讶。蓝月亮（一个日历月中的第二次满月）确实非常罕见，大约每2.7年才出现一次。

Algo que ocurre con tan poca frecuencia que resulta notable cuando sucede. Una luna azul (segunda luna llena en un mes calendario) es genuinamente rara, y ocurre aproximadamente una vez cada 2,7 años.

起こることが非常にまれで、起きたときには注目されるほど珍しいこと。ブルームーン（暦月内の2回目の満月）は実際にまれで、約2.7年に1回しか起こらない。

매우 드물게 일어나서 발생하면 놀라울 정도인 일을 의미합니다. 블루문(한 달에 두 번째 보름달)은 실제로 약 2.7년에 한 번 일어날 정도로 드문 현상입니다.

Examples

I only eat red meat once in a blue moon.
我很少吃红肉
Solo como carne roja muy de vez en cuando
赤身の肉はめったに食べない
붉은 고기는 아주 가끔만 먹어.
He visits once in a blue moon.
他很少来拜访
Viene de visita muy rara vez
彼はめったに訪ねてこない
그는 아주 가끔 한 번 찾아온다.
Once in a blue moon, we get a sunny day in November.
难得在十一月遇到晴天
De vez en cuando, tenemos un día soleado en noviembre
ごくまれに、11月に晴れの日がある
아주 드물게 11월에 맑은 날이 있다.

Pronunciation

/wʌns ɪn ə bluː muːn/

Usage Guide

Context: rarity, infrequency, exceptions

Tone: casual, descriptive

✓ Do Say

Once in a blue moon
千载难逢
De Pascuas a Ramos
めったにない
아주 가끔
Only once in a blue moon
非常偶尔才会
Solo muy de vez en cuando
ごくまれにしかない
극히 드물게

✗ Don't Say

Very common idiom
非常常见的习语
Expresión muy común
非常に一般的な慣用句
매우 흔한 관용구

Common Mistakes

None—universally understood

Origin & History

Dates from the 19th century. A 'blue moon' originally meant something absurd or impossible. The astronomical definition (second full moon in a month) came later. Actual blue-colored moons are extremely rare, caused by atmospheric particles.

Etymology: From rarity of blue-tinted moon appearances

First recorded: 19th century

Cultural Context

Era: 19th century onwards

Generation: All ages

Social background: Universal

Pop culture: Songs ('Blue Moon'); Common saying

Regional notes: Universal across English-speaking world.

Variations

Once in a blue moonBlue moon