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.
To execute its ruthless 66-pound weight loss program, the rear seats have been completely deleted, replaced by a massive structural strut brace that significantly stiffens the chassis. Peter Lyon, Forbes.com, 13 June 2026 Nicks on the edge or stiffened, curled rubber will leave streaks. Mary Marlowe Leverette, Southern Living, 12 June 2026 The moose flinched and stiffened. Fred Bear, Outdoor Life, 11 June 2026 Volkswagen’s premium Audi brand has lost much of its luster in recent years, dragged down by trade tariffs, stiffening competition and a patchy electric-vehicle roster. William Wilkes, Bloomberg, 8 June 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 17 Jun. 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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