catalase

from WordNet (r) 3.0 (2006)

catalase
    n 1: enzyme found in most plant and animal cells that functions
         as an oxidative catalyst; decomposes hydrogen peroxide into
         oxygen and water

from The Collaborative International Dictionary of English v.0.48

catalase \catalase\ n.
   an enzyme found in most plant and animal cells that functions
   as an oxidative catalyst; it decomposes hydrogen peroxide
   into hydrogen and water.
   [WordNet 1.5]