STIFFEN, verb transitive
1. To make stiff; to make less pliant or flexible; as, to stiffen cloth with starch.
He stiffened his neck and hardened his heart from turning to the Lord God of Israel. 2 Chronicles 36:13.
STIFFEN the sinews; summon up the blood.
2. To make torpid; as stiffening grief.
3. To inspissate; to make more thick or viscous; as, to stiffen paste.
STIFFEN, verb intransitive
1. To become stiff; to become more rigid or less flexible.
--Like bristles rose my stiffning hair.
2. To become more thick, or less soft; to be inspissated; to approach to hardness; as, melted substances stiffen as they cool.
The tender soil then stiffning by degrees--
3. To become less susceptible of impression; to become less susceptible of impression; to become less tender or yielding; to grow more obstinate.
Some souls, we see, grow hard and stiffen with adversity.