Simple Definition of stiffen
: to stop moving and become completely still especially because of fear, anger, etc.
: to become painful to move or use
: to become more severe or strong or to make (something) more severe or strong
Examples of stiffen
She stiffened when he grabbed her shoulder.
The dogs stiffened in alarm.
The law would stiffen penalties for tax evasion.
First Known Use of stiffen
Seen and Heard
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