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

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Example Sentences

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Recent Examples of stiffen To execute its ruthless 66-pound weight loss program, the rear seats have been completely deleted, replaced by a massive structural strut brace that significantly stiffens the chassis. —

Peter Lyon, Forbes.com, 13 June 2026 Nicks on the edge or stiffened, curled rubber will leave streaks. —

Mary Marlowe Leverette, Southern Living, 12 June 2026 The moose flinched and stiffened. —

Fred Bear, Outdoor Life, 11 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 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