HARD-AND-FAST Synonyms: 86 Similar and Opposite Words

hard-and-fast

adjective

ˌhärd-ᵊn-ˈfast

Definition of hard-and-fast

as in certain

having been established and usually not subject to change hard-and-fast rules that governed the corporate environment in those days included strictures regarding office dress that were rigidly enforced

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in unchangeable

not capable of changing or being changed hard-and-fast beliefs that are the rock-solid foundation of their religion

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Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of hard-and-fast There are no hard-and-fast rules on how to log a home run or whether a circus catch ought to be recorded as more than an out. — Jacob Feldman, Sportico.com, 24 Apr. 2026 Dogs bred for alertness or reactivity may be more attuned to sound, though this isn’t a hard-and-fast rule. — Jamie Cuccinelli, Martha Stewart, 7 Apr. 2026 There are no hard-and-fast rules for replacing a mattress. — Sharon Brandwein, USA Today, 3 Apr. 2026 One hard-and-fast rule to live by in this case? — Stacia Datskovska, Footwear News, 26 Jan. 2026 See All Example Sentences for hard-and-fast

Recent Examples of Synonyms for hard-and-fast

Adjective

Trump on Monday announced plans to impose a 50% tariff on certain Canadian imports, citing what officials called trade discrimination against American companies in the dairy, auto and alcohol industries.

— Bonny Chu, FOXNews.com, 22 July 2026
Now, after mounting the American League’s second-best record since June 1, the picture is less certain.

— Cody Stavenhagen, New York Times, 22 July 2026

Definition of certain

Adjective

Families can also create irrevocable trusts to remove countable assets towards Medicaid qualification, but remember, irrevocable trusts are usually unchangeable.

— Medora Lee, USA Today, 9 May 2026
Policies Vary by Location As generous as Aldi’s approach can be, there are a few places where the rules are solid and unchangeable.

— Jessica Safavimehr, Southern Living, 22 Apr. 2026

Definition of unchangeable

Adjective

Irish boxer Lee Reeves is in a critical but stable condition in hospital after his defeat via knockout in Dublin on Saturday, a Queensberry Promotions spokesperson has confirmed.

— Chris McKenna, New York Times, 2 Aug. 2026
The woman was transported to the hospital and remains in stable condition.

— Noah Haggerty, Los Angeles Times, 2 Aug. 2026

Definition of stable

Adjective

On just one unchanging set, an old-time concert hall designed by Rachel Hauck and made appropriately ominous, a tiny ensemble enacts a whole Greek tragedy of love and sacrifice that goes from the land of the living to the underworld and back.

— Wilson Chapman, IndieWire, 22 July 2026
There is a fallacy in thinking of languages as brute and unchanging facts, laid out distinctly like elements in the periodic table.

— Nikhil Krishnan, New Yorker, 20 July 2026

Definition of unchanging

Adjective

Driving his son’s final path himself, Urrutia was convinced that if the wrong-way detectors had been working that night, his son would still be alive.

— Brittany Wallman, Miami Herald, 31 July 2026
In the final moments of the movie, Holland’s Peter Parker runs into his former best friend Ned (Jacob Batalon) at a cafe.

— Jordan Moreau, Variety, 31 July 2026

Definition of final

Adjective

Loyalty programs can become harder to understand when members are confronted with dozens of offers that have little connection to the brand’s identity.

— Jeff Fromm, Forbes.com, 3 Aug. 2026
Miami’s roster Saturday was depleted as German Berterame is out on concussion protocol after a hard hit against Montreal that resulted in him exiting the field in an ambulance.

— Michelle Kaufman, Miami Herald, 2 Aug. 2026

Definition of hard

Browse Nearby Words

hard

hard-and-fast

hardback

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“Hard-and-fast.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hard-and-fast. Accessed 4 Aug. 2026.

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Synonyms of hard-and-fast

adjective

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