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Words and Their StoriesLearning Expressions with VOA
Processed with VS1Describe things that happen rarely, friends you seldom see, and time that seems to last forever.
VOA source audio
Source: VOA Learning English · Words and Their Stories
View original article & transcriptThe episode explains “once in a blue moon,” an informal way to say something happens very rarely. It also explores “drop off the face of the Earth” for someone who seems to disappear from contact, and “forever and a day” for an exaggeratedly long time. The article notes that the moon itself is not actually blue.
Cultural note: A “blue moon” has more than one astronomical definition. The VOA story describes an extra full moon in a season with four full moons and also notes the later popular calendar-month meaning of a second full moon in one month. The idiom draws on rarity, not a literal change in the moon’s color.
Keep exploringWhen was the last time you did something only once in a blue moon—or reconnected with someone after forever and a day?
Phrase guide · 4 expressions
Original explanations and examples, created for learners. Save a card for later or hear the phrase spoken by your browser.
Describe a rare habit, visit, or occurrence.
Meaning
Very rarely; only from time to time.
Tone & use
Informal and often playful; it emphasizes that something is unusual, not an exact schedule.
Example
“We order takeout once in a blue moon because we usually cook at home.”
Meaning
Not happening often.
Tone & use
A neutral adjective that is more formal and precise than “once in a blue moon.”
Example
“The train service is infrequent on Sundays, so check the timetable first.”
Explain that you have not heard from someone in a long time.
Meaning
Disappear or stop communicating, often for a surprisingly long time.
Tone & use
Informal and exaggerated; avoid it if the person’s absence could be serious or sensitive.
Example
“After graduation, my study partner seemed to drop off the face of the Earth.”
Express that a period feels extremely long.
Meaning
A very long time, often said with exaggeration.
Tone & use
Informal; commonly used for a wait or a period since something happened.
Example
“It feels like forever and a day since we all had dinner together.”
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