[1] : The Collaborative International Dictionary of English v.0.48

stiffen \stiff"en\, v. i.
   to become stiff or stiffer, in any sense of the adjective.
   1913 webster

         like bristles rose my stiffening hair.   --dryden.
   1913 webster

         the tender soil then stiffening by degrees. --dryden.
   1913 webster

         some souls we see,
         grow hard and stiffen with adversity.    --dryden.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

stiffen \stiff"en\, v. t. imp.  p. p. stiffened; p. pr. 
   vb. n. stiffening. see stiff.
   1. to make stiff; to make less pliant or flexible; as, to
      stiffen cloth with starch.
      1913 webster

            stiffen the sinews, summon up the blood. --shak.
      1913 webster

   2. to inspissate; to make more thick or viscous; as, to
      stiffen paste.
      1913 webster

   3. to make torpid; to benumb.
      1913 webster
see also:
stiffened stiffening stiff 

[3] : WordNet (r) 2.0

stiffen
     v 1: become stiff or stiffer; "he stiffened when he saw his boss
          enter the room" ant: loosen
     2: make stiff or stiffer; "stiffen the cream by adding
        gelatine" ant: loosen
     3: restrict; "tighten the rules"; "stiffen the regulations"
        syn: tighten, tighten up, constrain
see also:
loosen tighten tighten up constrain 

[4] : Moby Thesaurus II by Grady Ward, 1.0

59 moby thesaurus words for "stiffen":
   amplify, back, be tough, beef up, brace, brace up, buttress,
   case harden, charge, clot, coagulate, confirm, congeal,
   crystallize, electrify, endure, energize, fortify, galvanize,
   generate, gird, hang tough, harden, invigorate, jell, loop in,
   nerve, plug in, prop, refresh, reinforce, reinvigorate,
   restrengthen, rigidify, screw up, set, shock, shore up, short,
   short-circuit, solidify, steel, step down, step up, strengthen,
   support, sustain, switch off, switch on, tauten, temper, tense,
   thicken, tighten, toughen, trice up, turn off, turn on,
   undergird

Stiffen >> S Words
Stiffen, definition of term: Stiffen
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