Stiffen

//ˈstɪfən// verb

verb ·Uncommon ·College level

Definitions

Verb
  1. 1
    To make stiff. transitive

    "Criminal prosecutions of abusers are generally the responsibility of local authorities, but the act stiffened sentences for stalking under federal law."

  2. 2
    make stiff or stiffer wordnet
  3. 3
    To become stiff. intransitive

    "Bewildered by the unexpected greeting, my son stiffened, but managed a polite answer."

  4. 4
    become stiff or stiffer wordnet
  5. 5
    severely restrict in scope or extent wordnet

Synonyms

All synonyms
amplifybackbe toughbeef upbracebrace up

Antonyms

All antonyms
loosen

Example

More examples

"She felt him stiffen in surprise when he heard the news."

Etymology

From Middle English stifnen, equivalent to stiff + -en.

Related phrases

stiffen up

More for "stiffen"

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Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.