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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Example Sentences
Recent Examples of Synonyms for firm (up)
Verb
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The tiny liquid droplets in the fog can freeze instantly to any surface, including vehicles and road surfaces.—
CA Weather Bot,
Sacbee.com,
12 Jan. 2026 -
There’s roughly two and a half months left of the winter season, which means that there are plenty of chilly evenings, snow storms, and freeze warnings to look forward to.—
Amelia McBride,
Travel + Leisure,
11 Jan. 2026
Verb
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Parashat Va’era tells us that Pharaoh’s heart was hardened, but the Torah does not describe him as raging all the time.—
Rabbi Bruce D. Forman,
Sun Sentinel,
13 Jan. 2026
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Areas where light is let through cause the polymer at those locations to harden, while areas kept in the dark stay fluid.—
Paul Sisson,
San Diego Union-Tribune,
12 Jan. 2026
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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 20 Jan. 2026.
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