stiffen   (Sound)

The verb stiffen has 3 senses

• stiffen -- (become stiff or stiffer; "He stiffened when he saw his boss enter the room")


• stiffen -- (make stiff or stiffer; "Stiffen the cream by adding gelatine")


• stiffen, tighten, tighten up, constrain -- (restrict; "Tighten the rules"; "stiffen the regulations")