STIFFEN Synonyms: 9 Similar and Opposite Words

stiffen

verb

ˈsti-fən

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

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

Example Sentences

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 What began as breathlessness hardened into silicosis, an irreversible disease that stiffens the lungs until even ordinary movement becomes effort. —

Dr. Céline Gounder, CBS News, 12 Mar. 2026 After the deputies put him back into the chair, Mitchell’s body stiffened, with his legs straight in front of him and his head lolling back. —

USA Today, 8 Mar. 2026 Leaving them out for too long can cause the fibers to stiffen. —

Ashlyn Needham, Southern Living, 7 Mar. 2026 The machine dryer agitates the clothing and prevents fibers from stiffening during drying, which is why clothing comes out feeling soft. —

Emily Benda Gaylord, The Spruce, 23 Feb. 2026 See All Example Sentences for stiffen

Recent Examples of Synonyms for stiffen

strengthen

Verb

The Worldpay deal also bolstered Global Payments presence in Europe and strengthened some of its offerings such as e-commerce capabilities.

— Justin Zacks, CNBC, 27 Mar. 2026
Community Safety Commissioner Todd Barnette says the facility would strengthen the community and is essential to meet the requirements of the consent decree following the murder of George Floyd.

— Ubah Ali, CBS News, 27 Mar. 2026