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• hard-and-fast
  hard-and-fast

  adjective

  strongly binding; not to be set aside or violated.
• hard and fast
  hard and fast

  adjective

  (hard-and-fast when prenominal) (esp of rules) invariable or strict

hard-and-fast

American  

[hahrd-n-fast, -fahst] / ˈhɑrd nˈfæst, -ˈfɑst /

adjective

1. strongly binding; not to be set aside or violated.

   hard-and-fast rules.

   Synonyms:

   unambiguous, rigorous, inviolable, inflexible, precise, fixed

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hard and fast British  

adjective

1. (hard-and-fast when prenominal) (esp of rules) invariable or strict

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hard and fast Idioms  

1. Defined, fixed, invariable, as in We have hard and fast rules for this procedure. This term originally was applied to a vessel that has come out of water, either by running aground or being put in dry dock, and is therefore unable to move. By the mid-1800s it was being used figuratively.

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Other Word Forms

• hard-and-fastness
  noun

Etymology

Origin of hard-and-fast

First recorded in 1865–70

Example Sentences

See Examples For:

hard-and-fast hard and fast

"But a blanket hard-and-fast rule isn't helpful, because it doesn't really allow for the intricacies and the individualisation of what's really going on."

From BBC ● Sep. 17, 2026

But he said that it’s not clear whether this is a hard-and-fast rule.

From MarketWatch ● Sep. 4, 2026

In a well-known law review article, Justice Antonin Scalia—the court’s original originalist—argued that in addition or in connection to originalism, judges should create their own hard-and-fast rules.

From Slate ● May 5, 2026

There are no hard-and-fast rules about when a place name or other traditional description attached to a product becomes generic.

From The Wall Street Journal ● Apr. 6, 2026

But my parents didn't have hard-and-fast rules about our career aspirations.

From "Americanized" by Sara Saedi

Yet divisions are expected over how hard and fast to move.

From The Wall Street Journal ● Jun. 19, 2026

While there are no hard and fast criteria, the market’s behavior over the past two months certainly fits the bill, according to Bret Kenwell, U.S. investment analyst at eToro.

From MarketWatch ● May 26, 2026

You warned that what we believed to be hard and fast rules protecting the free press were really just soft norms.

From Slate ● Feb. 24, 2026

Vigorous exercise makes you breathe hard and fast.

From BBC ● Jan. 20, 2026

She broke right, running hard and fast toward the volcano and the mist- shrouded circle of mountains that bordered it.

From "Beauty Queens" by Libba Bray