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 Over time, smoking can narrow and stiffen blood vessels and accelerate cardiovascular disease. — Katia Hetter, CNN Money, 16 Sep. 2026 But after a quick touchdown drive to take a 34-27 lead, the Oregon defense stiffened, and closed out the win with back-to-back stops. — Ian Miller Outkick, FOXNews.com, 6 Sep. 2026 Bile rose in Evie’s throat and her body stiffened under his touch. — Literary Hub, 2 Sep. 2026 Offering a 35% incentive aimed at stiffening up jobs here and enticing post-production to relocate to the Golden State, AB 2319 is racing toward a vote in the state Senate by next week once the bill is in final shape. — Dominic Patten, Deadline, 20 Aug. 2026 See All Example Sentences for stiffen

Recent Examples of Synonyms for stiffen

strengthen

Verb

Since 2021 the company has also been intent on strengthening its distribution channels and showrooms across Asia, Europe and North America.

— Sofia Celeste, Footwear News, 15 Oct. 2026
The work is intended to help transfer specialized nuclear-submarine design knowledge, improve technical coordination and strengthen the industrial capabilities required to build and sustain advanced submarines over their operational lifetimes.

— Prabhat Ranjan Mishra, Interesting Engineering, 15 Oct. 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 16 Oct. 2026.

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Synonyms of stiffen

verb

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