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
Salt dries into white rings, while melting snow can cause uneven water stains that stiffen leather, dull suede, and discolor fabric.
—
Katie Cloyd, Martha Stewart, 6 Jan. 2026
Outrage from the left about that maneuver stiffened Democratic spirits for a confrontation in the fall.
—Niall Stanage, The Hill, 31 Dec. 2025
Cream of tartar or 1/4 teaspoon lemon juice can be used to help the meringue stiffen.
—Caron Golden, San Diego Union-Tribune, 24 Dec. 2025
Also, imperceptibly at first, aerobic capacity begins to lessen, flexibility decreases, ligaments stiffen.
—Sally Jenkins, The Atlantic, 18 Dec. 2025
See All Example Sentences for stiffen
Katie Cloyd, Martha Stewart, 6 Jan. 2026
Outrage from the left about that maneuver stiffened Democratic spirits for a confrontation in the fall.
—Niall Stanage, The Hill, 31 Dec. 2025
Cream of tartar or 1/4 teaspoon lemon juice can be used to help the meringue stiffen.
—Caron Golden, San Diego Union-Tribune, 24 Dec. 2025
Also, imperceptibly at first, aerobic capacity begins to lessen, flexibility decreases, ligaments stiffen.
—Sally Jenkins, The Atlantic, 18 Dec. 2025
See All Example Sentences for stiffen
Recent Examples of Synonyms for stiffen
strengthen
Verb
-
This increases demand for low-carbon products, stimulates decarbonisation and strengthens interest in DRI/HBI feedstock, which Ukraine can supply.—
CBS News,
CBS News,
23 Jan. 2026
-
When people feel safe expressing themselves openly and honestly, trust is strengthened on both sides, and collaboration becomes more productive.—
Britney Porter,
Forbes.com,
23 Jan. 2026
Cite this Entry
“Stiffen.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/stiffen. Accessed 31 Jan. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
