stiffen up

Verb

Meaning

stiffen up (third-person singular simple present stiffens up, present participle stiffening up, simple past and past participle stiffened up)

To become rigid, tense or stiff.

Source: en.wiktionary.org

Synonyms

freeze

Close letter words and terms

stiff-upper-lippery stiffen stiffen the resolve of stiffener stiffening stiffening order