The Collaborative International Dictionary of English v.0.48:

metalorganic \met`al*or*gan"ic\, a. [Metal, L. metallum + E.
   organic.] (Chem.)
   Pertaining to, or denoting, any one of a series of compounds
   of certain metallic elements with organic radicals; as, zinc
   methyl, sodium ethyl, etc.; now usually organometallic.
   [Written also metallorganic.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Metallorganic \Met`al*lor*gan"ic\, a.
   Metalorganic.
   [1913 Webster]