STIFFEN Synonyms: 9 Similar and Opposite Words

stiffen

verb

ˈsti-fən

Definition of stiffen

as in to strengthen

to make more harsh, uncompromising, or severe plans to further stiffen the already onerous requirements for admission to the elite military unit

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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.

Recent Examples of stiffen For seven-and-a-half years, Ladd had dealt with idiopathic pulmonary fibrosis (IPF), a progressive lung disease that stiffens and scars the lungs. — Helen Carefoot, Flow Space, 24 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 Major media companies operating traditional linear networks have been under pressure in recent years amid stiffening competition from large tech rivals as programming migrates to streaming. — Dade Hayes, Deadline, 18 June 2026 Pulisic played a dynamic first half in the Americans' historic 4-1 victory over Paraguay to open their home World Cup nearly two weeks ago, but the AC Milan midfielder came off at halftime after an injury from training stiffened up. — ABC News, 24 June 2026 See All Example Sentences for stiffen

Recent Examples of Synonyms for stiffen

strengthen

Verb

Manucurist formulates its masks with panthenol, a form of vitamin B5, to hydrate and strengthen dry nails over time, reducing breakage.

— Irene Richardson, InStyle, 4 July 2026
The only way to preserve our republic is to strengthen the pillars of our present with the mortar of our past.

— Gustavo Arellano, Los Angeles Times, 4 July 2026

Definition of strengthen

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stiffed

stiffen

stiffened

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“Stiffen.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/stiffen. Accessed 8 Jul. 2026.

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Synonyms of stiffen

verb

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