1 [intransitive] if you stiffen, your body suddenly becomes firm, straight, or still because you feel angry or anxious [≠ relax]:
He touched her, and she stiffened.
2 [intransitive and transitive] to become stronger, more severe, or more determined, or to make something do this:
a campaign to stiffen rules against drunk driving
Their opposition only stiffened my resolve.
3 [intransitive] also stiffen up to become painful and difficult to move:
His joints had stiffened.
My back had stiffened up.
4 [transitive] to make material stiff so that it will not bend easily

Dictionary results for "stiffen"
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