Source : Webster's Revised Unabridged Dictionary (1913)

Germicide \Ger"mi*cide\ (j[~e]r"m[i^]*s[imac]d), a. [Germ + L.
   caedere to kill.] (Biol.)
   Destructive to germs; -- applied to any agent which has a
   destructive action upon living germs, particularly bacteria,
   or bacterial germs, which are considered the cause of many
   infectious diseases. -- n. A germicide agent.

Source : WordNet®

germicide
     n : an agent (as heat or radiation or a chemical) that destroys
         microorganisms that might carry disease [syn: {disinfectant},
          {antimicrobic}, {antimicrobial}]