What is the saying for rare event?

The primary saying for a rare event is "Once in a blue moon." This idiom vividly describes occurrences that happen very infrequently.

Understanding Idioms for Rare Events

Idioms are phrases or expressions whose meaning cannot be deduced from the literal meanings of its words. They often paint a picture that helps convey a specific concept. When referring to events that seldom or perhaps never occur, specific idioms come to mind.

Once in a Blue Moon

This popular idiom refers to something that happens very rarely. The term "blue moon" itself refers to the second full moon within a single calendar month, which is an uncommon astronomical event, occurring roughly every two to three years.

• Meaning: An event that is highly infrequent.
• Usage: It signifies an exceptional or uncommon occurrence.

Examples:

• "My sister, who lives abroad, visits us once in a blue moon."
• "We only get a snow day here once in a blue moon."

Other Related Sayings for Improbability

While "Once in a blue moon" directly signifies rarity, other idioms exist to describe events that are extremely unlikely or might never happen, bordering on impossibility.

• Don't hold your breath: This idiom suggests that if you wait for a particular thing to happen, you will be waiting for an extremely long time, perhaps indefinitely, implying it's highly improbable or will never occur. The implication is that you would die from holding your breath before the event comes to pass.
  • Meaning: Something is very unlikely to happen, or will take an extremely long time if it does.
  • Example: "He said he'd pay me back next week, but don't hold your breath."

Here's a quick reference table for these idioms:

For more expressions related to events of improbability, you can explore various idioms of improbability. These phrases enrich language by providing colorful ways to describe how often, or how seldom, things occur.