dicarboxylyl /ˌdaɪ.kɑːrˈbɒk.sɪ.lɪl/ noun1 •A bivalent radical derived from a dicarboxylic acid by removing the hydroxyl groups from both carboxyl groups.In one reaction (pyrolysis of acetylene dicarboxylyl fluoride), the volatile products condensed to a stable polymeric film; however, the film was not perfluorinated. — 1962 formsdicarboxylyls