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

petrify \pet"rify\ pe^t"ri^fimac, v. t. imp.  p. p.
   petrified; p. pr.  vb. n. petrifying. l. petra rock,
   gr. pe`tra akin to pe`tros a stone + -fy: cf. f.
   p'etrifier. cf. parrot, petrel, pier.
   1. to convert, as any animal or vegetable matter, into stone
      or stony substance; as, petrified wood.
      1913 webster

            a river that petrifies any sort of wood or leaves.
                                                  --kirwan.
      1913 webster

   2. to make callous or obdurate; to transform, as by
      petrifaction; as, to petrify the heart. young. "petrifying
      accuracy." --sir w. scott.
      1913 webster

            and petrify a genius to a dunce.      --pope.
      1913 webster

            a hideous fatalism, which ought, logically, to
            petrify your volition.                --g. eliot.
      1913 webster

   3. to paralyze, especially with fear; to stupefy; as, she was
      petrified by the sight of the bear in her tent.
      pjc

            the poor, petrified journeyman, quite unconscious of
            what he was doing.                    --de quincey.
      1913 webster
see also:
petrified petrifying parrot petrel pier 

[2] : WordNet (r) 2.0

petrifying
     adj : paralyzing with terror

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

21 moby thesaurus words for "petrifying":
   bloodcurdling, hair-raising, hardening, indurative, paralyzing,
   petrifactive, stunning, stupefying, terrifying, terror,
   terror-bearing, terror-breathing, terror-breeding, terror-bringing,
   terror-fraught, terror-giving, terror-inspiring, terror-striking,
   terrorful, terroristic, toughening

Petrifying >> P Words
Petrifying, definition of term: Petrifying
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