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

Relevance

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

Synonyms & Similar Words

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

Some support certain safety proposals at the federal, state, and even international levels.

— Ashley Gold, semafor.com, 15 Sep. 2026
Contract terms, vendor requirements, safety programs and business continuity planning can reduce either the likelihood or financial severity of certain losses before financing enters the equation.

— Randy Sadler, Forbes.com, 15 Sep. 2026

Definition of certain

Adjective

Her mother, originally from Sinaloa, does workers’ compensation insurance, which provided a stable income and allowed her partner to pursue acting.

— Carlos Aguilar, Los Angeles Times, 18 Sep. 2026
When many defects were present, the electrons became locked into an unexpectedly stable Wigner solid with irregular and disordered patterns.

— Georgina Jedikovska, Interesting Engineering, 18 Sep. 2026

Definition of stable

Adjective

The cultural issues reported in stories like these are no doubt real, but framing them as expressions of an enduring Southern Bible Belt seems to imagine religion as unchanging, timeless.

— John Hayes, The Conversation, 9 Sep. 2026
Of recognizing the Sisyphean task ahead, the endless, unchanging road diminishing in the distance, and taking another step anyway.

— Emily Temple, Literary Hub, 18 Aug. 2026

Definition of unchanging

Adjective

There’s a passage in the final movement when the full orchestra, reinforced by trumpets, trombones, tuba, and a thunder roll of timpani, clamber up to a teeth-rattling fortissimo.

— Justin Davidson, Vulture, 18 Sep. 2026
The House passed the bill in a 262 to 159 vote on the final day that the lower chamber is in session before lawmakers leave Washington until after Election Day.

— Caitlin Yilek, CBS News, 17 Sep. 2026

Definition of final

Adjective

Home loans Because fixed 15- and 30-year mortgage rates tend to track the yield on the 10-year Treasury note and broader bond-market conditions rather than the federal funds rate directly, homeowners won't be affected immediately by a Fed rate hike.

— Jessica Dickler, CNBC, 16 Sep. 2026
Users also want covers that can serve as accessories for content creation, such as for a workout that requires a fixed camera angle.

— New Atlas, New Atlas, 14 Sep. 2026

Definition of fixed

Browse Nearby Words

hard

hard-and-fast

hardback

See all Nearby Words

Cite this Entry

Style

“Hard-and-fast.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/hard-and-fast. Accessed 22 Sep. 2026.

Copy Citation

Synonyms of hard-and-fast

adjective

Example Sentences

Browse Nearby Words

Cite this Entry

More from Merriam-Webster

Word of the Day

nemesis

Popular in Grammar & Usage

Why do we use apostrophes to show possession?

Merriam-Webster’s Great Big List of Words You Love to Hate

The Exceptions of '-s' and '-es' Plurals

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Popular in Wordplay

9 Words That Sound Like Insults But Aren't

Back to School Vocabulary

Words from the 'Odyssey'

14 Phobias You Probably Haven't Heard Of

The Words of the Week - Sept. 18

Popular

Why do we use apostrophes to show possession?

9 Words That Sound Like Insults But Aren't

Back to School Vocabulary

Games & Quizzes