list of synonyms of word stiffen

• change (generic term)
• loosen (antonym)

• change (generic term)
• alter (generic term)
• modify (generic term)
• loosen (antonym)

• tighten
• tighten up
• constrain
• restrict (generic term)
• restrain (generic term)
• trammel (generic term)
• limit (generic term)
• bound (generic term)
• confine (generic term)
• throttle (generic term)