(stiffens, stiffening, stiffened)
1.
If you stiffen, you stop moving and stand or sit with muscles that are suddenly tense, for example because you feel afraid or angry.
Ada stiffened at the sound of his voice...
VERB: V
2.
If your muscles or joints stiffen, or if something stiffens them, they become difficult to bend or move.
The blood supply to the skin is reduced when muscles stiffen.
VERB: V, also V n
•
Stiffen up means the same as
stiffen.
These clothes restrict your freedom of movement and stiffen up the whole body...
PHRASAL VERB: V P n (not pron)
3.
If something such as cloth is stiffened, it is made firm so that it does not bend easily.
This special paper was actually thin, soft Sugiwara paper that had been stiffened with a kind of paste...
VERB: usu passive, be V-ed