Find Antonyms
stiffen Antonyms
Opposite of stiffen
Because the opposite of stiffen shifts with each meaning, the 11 antonyms and opposite words below are separated across 3 exact definitions and ranked by contrast strength.
• verb (Context 1)
To make or become rigid, firm, or inflexible.
Usage Example
"The tailor used heavy interfacing to soften the collar of the jacket."
Strongest
soften
Strong
loosen
limber
slacken
• verb (Context 2)
To suddenly tense one's body or muscles, especially in reaction to fear, shock, or anger.
Usage Example
"She felt her shoulders relax as she heard footsteps approaching in the dark hallway."
Strongest
relax
Strong
unbend
slump
• verb (Context 3)
To make or become stronger, more severe, or more resolute (such as penalties, resistance, or wind).
Usage Example
"The unexpected setback only served to weaken their resolve to complete the expedition."
Strongest
weaken
Strong
ease
relent
waver
Similar words to stiffen
Words similar to stiffen shift depending on context. Common synonyms include:
tense
strengthen
harden
rigidify
tauten
tighten
toughen
firm
Cite this Entry
Wordmom. (2026). Antonyms for Stiffen. In Wordmom Thesaurus. Retrieved Nov 5, 2026, from https://wordmom.com/antonyms/stiffen