The Collaborative International Dictionary of English v.0.48:

Extinguish \Ex*tin"guish\ ([e^]ks*t[i^][ng]"gw[i^]sh), v. t.
   [imp. & p. p. Extinguished([e^]ks*t[i^][ng]"gw[i^]sht); p
   pr. & vb. n. Extinguishing.] [L. extinguere, exstinguere;
   ex out + stinguere to quench. See Distinguish, Finish.]
   1. To quench; to put out, as a light or fire; to stifle; to
      cause to die out; to put an end to; to destroy; as, to
      extinguish a flame, or life, or love, or hope, a pretense
      or a right.
      [1913 Webster]

            A light which the fierce winds have no power to
            extinguish.                           --Prescott.
      [1913 Webster]

            This extinguishes my right to the reversion.
                                                  --Blackstone.
      [1913 Webster]

   2. To obscure; to eclipse, as by superior splendor.
      [1913 Webster]

            Natural graces that extinguish art.   --Shak
      .
      [1913 Webster]

WordNet (r) 3.0 (2006):

extinguishing
    n 1: the act of extinguishing; causing to stop burning; "the
         extinction of the lights" [syn: extinction,
         extinguishing, quenching]