The Collaborative International Dictionary of English v.0.48:

Cyamelide \Cy*am"e*lide\ (s[-i]*[a^]m"[-e]*l[i^]d or -l[imac]d;
   104), n. (Chem.)
   A white amorphous substance, regarded as a polymeric
   modification of isocyanic acid.
   [1913 Webster]