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

intransitive verb

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

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.
The men’s Run 900 Ultra Black Shorts feature integrated Rheon technology, a reactive polymer that remains soft at rest but stiffens under pressure. Alexandra Harrell, Footwear News, 10 Apr. 2026 June stiffened, a pillar of ice. Meredith Maran, Los Angeles Times, 8 Apr. 2026 Officials this year have increased restrictions on flying drones and stiffened the penalties for their unauthorized use—including jail time. Andrew Nusca, Fortune, 6 Apr. 2026 The woman—Rose, apparently—stiffens slightly. Danielle Parker, CBS News, 2 Apr. 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

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Cite this Entry

“Stiffen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/stiffen. Accessed 11 Apr. 2026.

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 noun

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