verb (used with object)
to make stiff.
verb (used without object)
to become stiff.
to become suddenly tense, rigid, or taut, as in bracing oneself for or drawing back from shock, fear, or displeasure: He stiffened, expecting to hear the worst.

1490–1500; stiff + -en1

overstiffen, verb
unstiffened, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To stiffen
World English Dictionary
stiffen (ˈstɪfən)
1.  to make or become stiff or stiffer
2.  (intr) to become suddenly tense or unyielding

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Example sentences
Stiffen the requirements for entry to graduate school.
They stay perfectly still while resting and when disturbed they raise their
  head and stiffen their body, simulating a branch.
He still caressed the sheep, but it was dead and beginning to stiffen.
For example, they're missing a bone found in monkeys and humans, which helps to
  stiffen our feet.
Copyright © 2014, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature