stiff·en | \ˈsti-fən \
stiffened; stiffening\ˈsti-fə-niŋ, ˈstif-niŋ \

Definition of stiffen 

intransitive verb

: to become stiff or stiffer

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Other Words from stiffen

stiffener \ˈsti-fə-nər, 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

While that argument won't sway Republicans, their strategy could stiffen Democratic resolve to oppose the nominee. Kevin Freking,, "What to expect in the Supreme Court confirmation battle," 9 July 2018 While that argument won’t sway Republicans, their strategy could stiffen Democratic resolve to oppose the nominee. Kevin Freking, The Seattle Times, "What to expect in the Supreme Court confirmation battle," 9 July 2018 Peach preserves flavor smooth-drinking black tea that’s brightened with a squeeze of lemon and stiffened with a shot of Bulleit. Ashleigh Spitza, Milwaukee Journal Sentinel, "Keep it simple and seasonal in the kitchen during summer," 7 June 2018 The Danish company Really, in partnership with the Danish textile brand Kvadrat, returned to Milan for a second year with a show of furnishings made from discarded denim and white cotton laundry fibers stiffened with a binder. New York Times, "Trends in Design and Home Furnishings," 8 May 2018 With bipartisan support, the Legislature stiffened age requirements for gun purchases and outlawed bump stocks like the device used by the Las Vegas mass shooter in October. Jacob Gershman, WSJ, "How Many States Will Pass Gun-Control Laws Before Recess?," 2 Apr. 2018 Conversely, those on the other side have stiffened Prop. Dan Walters, San Francisco Chronicle, "Any assault on tax-cutting Prop. 13 is still an uphill fight," 29 Mar. 2018 The corset of the 1880s was an armpit-to-hip garment stiffened with whalebone stays, which helped the hips support heavy skirts that hung from the waist. Aaron Gilbreath, Longreads, "The Wheel, the Woman, and the Human Body," 6 July 2018 The solution came from stiffening the robot’s transmission and installing soft pads on the robot’s front legs. David Grossman, Popular Mechanics, "Harvard Robotic Cockroach Walks Underwater," 3 July 2018

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

1 Sep 2018

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 \
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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Comments on stiffen

What made you want to look up stiffen? Please tell us where you read or heard it (including the quote, if possible).


to reject or criticize sharply

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