Pronunciation: /ˈstɪfən/
verb to make or become stiff or rigid
A1 When I get scared, my muscles stiffen up.
A2 The cold weather caused the metal to stiffen and become brittle.
B1 The new regulations will likely stiffen penalties for companies that violate environmental laws.
B2 The government's decision to stiffen border controls has sparked controversy among citizens.
C1 The company's policy on employee conduct has gradually stiffened over the years.
C2 The athlete's training regimen has helped stiffen his resolve to win the upcoming championship.
formal The metal rods are designed to stiffen the structure and prevent any bending.
informal If you don't want the cake to collapse, you need to let it cool and stiffen before adding the frosting.
slang I could feel my muscles stiffen up after that intense workout.
figurative His resolve only seemed to stiffen in the face of adversity.
stiffened
stiffens
stiffer
stiffest
stiffen
will stiffen
have stiffened
is stiffening
stiffen
stiff
to stiffen
stiffening
stiffened