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

hard-and-fast

adjective

ˌhärd-ᵊn-ˈfast

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 But even in the absence of hard-and-fast rules and guardrails on how AI can be used in schools, education policymakers identified a number of ethical concerns raised by the technology’s spread, including student safety, data privacy and negative impacts on student learning. —

Janice Mak, The Conversation, 22 Jan. 2026 This was my hard-and-fast belief — up until the trailer for The Sheep Detectives was released on December 18. —

Fran Hoepfner, Vulture, 18 Dec. 2025 There’s no hard-and-fast rule, and if someone tells you there is? —

Natalie Krebs, Outdoor Life, 28 Aug. 2025 Final Thoughts Like most decision-making in business, there are no hard-and-fast rules. —

Lisa Zeiderman, Forbes.com, 1 Aug. 2025 See All Example Sentences for hard-and-fast

Recent Examples of Synonyms for hard-and-fast

Adjective

That’s part of the lip-smacking quality of it all — the idea that certain movie characters deserve to have their limbs bitten off.

— Owen Gleiberman, Variety, 11 Apr. 2026
Due to an increase in passenger volume, parking availability may be at or near capacity at certain times throughout the day.

— Staff Report, Hartford Courant, 11 Apr. 2026