Third-person singular simple present indicative form of stiffen.(verb)
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Use "stiffens" in a sentence
"According to The New York Times, scientists at Case Western University have created a material that stiffens from a soft state when stimulated."
"In the case of Woolf, Elshtain stiffens her tone and accuses her of seeking to 'de-realise' rather than realise the citizen with her outsider, peaceful separationism."
"But the influence of "our Hindenburg," as he is often affectionately called, is wider than the east; the magic of his name stiffens the deadline in the west, and the man in the street, whose faith is great, feels sure that when he has fought his last great battle in the east the turn of the French and English will come."