firm (up)

verb

Definition of firm (up)next
as in to freeze
to become physically firm or solid wait for the modeling clay to firm up before handling the finished pot

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Recent Examples of Synonyms for firm (up)
  1. freeze
  2. harden
Verb
  • Ice•ology trays use a slow-freezing process designed to separate impurities and air bubbles from the ice, creating crystal-clear cubes that elevate cocktails, mocktails and everyday beverages.
    — ABC News, ABC News, 24 Oct. 2026
  • Barnes is cold-based, and thus frozen directly onto the bedrock beneath it, which prevents it from sliding.
    — Jacek Krywko, ArsTechnica, 24 Oct. 2026
Definition of freeze
Verb
  • The building materials are fire-resistant, as are the windows, and the eaves are fire-hardened as well.
    — Steve Lopez, Los Angeles Times, 24 Oct. 2026
  • The process, called cured-in-place pipe lining, involves inserting a flexible liner into the old pipe, inflating it and hardening it in place.
    — Nicole Buss, Sacbee.com, 22 Oct. 2026
Definition of harden
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.

Browse Nearby Words

firms (up)
firm (up)
first
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Cite this Entry

“Firm (up).” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/firm%20%28up%29. Accessed 25 Oct. 2026.

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