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

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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

Some states, including Maryland, prohibit certain hospitals from requiring prepayment simply to avoid offering financial assistance.

— Julie Appleby, CBS News, 12 Aug. 2026
Rather than relying purely on attacking returns or clean sheets, players can now earn additional FPL points by reaching certain defensive thresholds.

— Abdul Rehman, New York Times, 12 Aug. 2026

Definition of certain

Adjective

Think of it as giving a huge group of devices the same unchangeable password.

— Kurt Knutsson, FOXNews.com, 31 July 2026
An organization that has seen its problem and defined it as unchangeable has pre-agreed that the one thing that would work is the one thing that cannot be done.

— Vibhas Ratanjee, Forbes.com, 31 July 2026

Definition of unchangeable

Adjective

That has left oil supplies being released in intermittent waves, rather than returning to the stable, steady flow seen in the past.

— , CNBC, 10 Aug. 2026
Unlike many other regions, Australian largetooth sawfish appear to have maintained relatively stable genetic diversity since at least the 1960s.

— Melissa Cristina Márquez, Forbes.com, 10 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

A bit of final lagniappe handed to the BKTrustee was a ruling that all the assets of the Children's Trust was determined to be part of the Kittrells' bankruptcy estate.

— Jay Adkisson, Forbes.com, 7 Aug. 2026
Minnesota stopped a four-game skid and moved within one-half game of Texas for the final AL wild card, tied with AL Central rival Cleveland.

— CBS News, CBS News, 7 Aug. 2026

Definition of final

Adjective

Certainly Larimore is pointing out that hard times lead to hard truths and hard decisions.

— Christopher Arnott, Hartford Courant, 10 Aug. 2026
Perseus Rising in the northeast after dark, Perseus is not the easiest constellation to make sense of, but its rich star fields are hard to miss.

— Jamie Carter, Forbes.com, 10 Aug. 2026

Definition of hard

Browse Nearby Words

hard

hard-and-fast

hardback

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Style

“Hard-and-fast.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hard-and-fast. Accessed 13 Aug. 2026.

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Synonyms of hard-and-fast

adjective

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