As nouns the difference between organometallic and diphenylacetylene is that organometallic is (chemistry) any organometallic compound while diphenylacetylene is (organic chemistry) a colourless crystalline material widely used as a building block in organic chemistry and as a ligand in organometallic chemistry.

As an adjective organometallic is (chemistry) of, or relating to organic compounds having a metal atom directly bonded to a carbon atom.