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 However, the collagen jelly mask became the exception to my hard-and-fast rule. — Irene Richardson, InStyle, 6 June 2026 There’s no hard-and-fast rule on how physically close a witness should be under recall status, and these restrictions are up to a judge. — Frank Landymore, Futurism, 14 May 2026 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 See All Example Sentences for hard-and-fast

Recent Examples of Synonyms for hard-and-fast

Adjective

Albion, newly relegated from the Premier League and promotion favourites, were certain to come to town and win this local derby on the opening day.

— Amitai Winehouse, New York Times, 9 Sep. 2026
People with thyroid disease, kidney, liver or heart problems, or those taking NSAIDs, opiate pain medications or certain antidepressants can actually take in too much water.

— Hanna Wickes, Sacbee.com, 8 Sep. 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

Nuclear power, where viable, can offer another source of relatively stable generation costs.

— Nana Menya Ayensu, semafor.com, 7 Sep. 2026
Don also taught his son how to be a light for people who need him, how to be level-headed and stable and how to deal with adversity.

— Colleen Kane, Chicago Tribune, 6 Sep. 2026

Definition of stable

Adjective

In the final episode of her new Netflix reality show Earle Meets World, which aired in full on Friday, the 25-year-old shared a glimpse of what was happening behind the scenes after Cooper called her out in a TikTok post on April 13.

— Daysia Tolentino, Entertainment Weekly, 4 Sep. 2026
Steinem spent her final years continuing to write, her representatives noted Thursday, including her forthcoming book An Unexpected Life.

— Daniel Kreps, Rolling Stone, 3 Sep. 2026

Definition of final

Adjective

Because living expenses form a critical part of retirement planning, the study operated under the baseline assumption that retirees live on a fixed income.

— Gagandeep Singh, Sacbee.com, 2 Sep. 2026
The precise spectacle changes daily because balloons travel with the wind rather than following a fixed route.

— Scott Campbell, Condé Nast Traveler, 2 Sep. 2026

Definition of fixed

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 9 Sep. 2026.

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Synonyms of hard-and-fast

adjective

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