stiffen

verb

stiff·​en ˈsti-fən How to pronounce stiffen (audio)
stiffened; stiffening ˈsti-fə-niŋ How to pronounce stiffen (audio)
ˈstif-niŋ
Synonyms of stiffennext

transitive verb

: to make stiff or stiffer

intransitive verb

: to become stiff or stiffer
stiffener
ˈsti-fə-nər How to pronounce stiffen (audio)
ˈstif-nər
noun

Synonyms of stiffen

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Examples of stiffen in a Sentence

She stiffened when he grabbed her shoulder. The dogs stiffened in alarm. The law would stiffen penalties for tax evasion.
Recent Examples on the Web
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.
Texas stiffened and took the 21-point lead to the locker room. — ABC News, 24 Oct. 2026 The Smart Go's polyurethane airbag uses a patented diaphragm technology and a layered internal structure to stiffen up when it's deployed. — New Atlas, 22 Oct. 2026 Proposition 132 attempts to address these concerns by stiffening legal penalties. — Joshua Barocas, The Conversation, 16 Oct. 2026 Avoiding harsh chemicals like bleach, fabric softeners, and the like will help keep your robe soft and absorbent as these formulas could break down the fabric, leave behind fabric-stiffening residue, or cause pilling and other concerns. — Patricia Shannon, Southern Living, 26 Sep. 2026 See All Example Sentences for stiffen

Word History

First Known Use

15th century, in the meaning defined at transitive sense

Time Traveler
The first known use of stiffen was in the 15th century

Rhymes for stiffen

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Browse Nearby Words

stiff drink
stiffen
stiffener
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Cite this Entry

“Stiffen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/stiffen. Accessed 27 Oct. 2026.

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Kids Definition

stiffen

verb
stiff·​en ˈstif-ən How to pronounce stiffen (audio)
stiffened; stiffening -(ə-)niŋ How to pronounce stiffen (audio)
: to make or become stiff or stiffer
stiffener
-(ə-)nər How to pronounce stiffen (audio)
noun
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