The Collaborative International Dictionary of English v.0.48:

Hypostasize \Hy*pos"ta*size\, v. t.
   To make into a distinct substance; to conceive or treat as an
   existing being; to hypostatize. [R.]
   [1913 Webster]

         The pressed Newtonians . . . refused to hypostasize the
         law of gravitation into an ether.        --Coleridge.
   Hypostatic