Stiffen

Synonyms of stiffen

• strengthen
• solidify
• harden

Antonyms of stiffen

• soften
• loosen
• relax

Collocations of stiffen

stiffen muscles

Frequency: 80 %

He felt his muscles stiffen as he prepared for the race.

stiffen resolve

Frequency: 70 %

The difficult situation only served to stiffen her resolve.

stiffen posture

Frequency: 60 %

She stiffened her posture as she walked into the room, trying to appear confident.

stiffen upper lip

Frequency: 50 %

In times of crisis, she would always stiffen her upper lip and face the challenge head-on.

Idiomatic Expressions for stiffen

• Phrase: stiffen up
  Meaning: to become rigid or tense, often due to fear, anxiety, or cold
  Usage: He stiffened up when he heard a loud noise behind him.