as in to freeze
to become physically firm or solid
wait for the modeling clay to firm up before handling the finished pot
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Example Sentences
Recent Examples of Synonyms for firm (up)
Verb
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In 2057, Earth is freezing as the sun has begun to die.—
Los Angeles Times,
Los Angeles Times,
21 Feb. 2026 -
The National Weather Service warns residents of the negative effect of frost and freeze conditions on crops and other sensitive vegetation.—
Veronica Fernandez-Alvarado
Updated February 20,
Sacbee.com,
21 Feb. 2026
Verb
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As if the wide-eyed innocent who arrived here has been hardened.—
Dana O’Neil,
CNN Money,
20 Feb. 2026
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Florida lawmakers are assigning no new money this year for My Safe Florida Home, the popular home-hardening program that awards $10,000 grants to help Floridians upgrade their windows and doors.—
Lawrence Mower,
Miami Herald,
19 Feb. 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 23 Feb. 2026.
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