stiff·​en | \ ˈsti-fən How to pronounce stiffen (audio) \
stiffened; stiffening\ ˈsti-​fə-​niŋ How to pronounce stiffening (audio) , ˈstif-​niŋ \

Definition of stiffen

intransitive verb

: to become stiff or stiffer

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Other Words from stiffen

stiffener \ ˈsti-​fə-​nər How to pronounce stiffener (audio) , ˈstif-​nər \ noun

Synonyms & Antonyms for stiffen


harden, harshen, strengthen, toughen


ameliorate, ease

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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.
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Recent Examples on the Web

In May, Germany’s Federal Financial Supervisory Authority (BaFin) published an order for N26, which requires the neobank to stiffen its processes for money laundering prevention. John Detrixhe, Quartz, "As Deutsche Bank retreats from the US, a German fintech is launching there," 11 July 2019 One common reason for this is that blood vessels begin to stiffen as people age. Ladan Nikravan Hayes,, "‘Let’s Talk’: What causes high blood pressure and how to lower it," 9 July 2019 Republicans filed several measures designed to stiffen penalties for violations of gun laws. Washington Post, "Gun debate hits full throttle in Richmond as legislature convenes," 9 July 2019 Trying to govern by threat and blunt force isn’t really governing at all, and if enough bluffs get called, the players on the other side of the table tend to stiffen their spines. Timothy L. O'brien, The Denver Post, "O’Brien: Donald Trump’s failures — like his abandoned tariffs on Mexico — make him even more dangerous," 10 June 2019 Mr Ebrard will vow to stiffen controls in the future and boost border-security funding by $250m in the next 12 months. The Economist, "Mexico has little choice but to placate Donald Trump," 6 June 2019 Mr Imamoglu’s success ought to stiffen their resolve. The Economist, "Opponents of Turkey’s erratic president should try harder," 29 June 2019 After experiencing this fear, her right arm stiffened and rose unnaturally. Suzanne O’sullivan, WSJ, "Confessions of the Miswired Brain," 5 Oct. 2018 The ribbon stiffened and relaxed in a strange nonchaotic pattern, bringing to life the mathematical discovery from six years earlier. Quanta Magazine, "Strange Stars Pulse to the Golden Mean," 10 Mar. 2015

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'stiffen.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of stiffen

15th century, in the meaning defined at transitive sense

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Statistics for stiffen

Last Updated

21 Jul 2019

Look-up Popularity

Time Traveler for stiffen

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

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More Definitions for stiffen



English Language Learners Definition of stiffen

: to stop moving and become completely still especially because of fear, anger, etc.
: to become painful to move or use
: to become more severe or strong or to make (something) more severe or strong


stiff·​en | \ ˈsti-fən How to pronounce stiffen (audio) \
stiffened; stiffening

Kids Definition of stiffen

1 : to make or become stiff or stiffer The paper stiffened as it dried.
2 : to become tense and still He stiffened with suspicion.

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More from Merriam-Webster on stiffen

Rhyming Dictionary: Words that rhyme with stiffen

Thesaurus: All synonyms and antonyms for stiffen

Spanish Central: Translation of stiffen

Nglish: Translation of stiffen for Spanish Speakers

Britannica English: Translation of stiffen for Arabic Speakers

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