Relating to or dealing with shaping or modeling, Easily influenced; impressionable, Able to change and adapt, especially by acquiring alternative pathways for sensory perception or motor skills. Used of the central nervous system, noun_ Any of various organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments used as textile fibers, The art. of modeling or molding; sculpture, The commercial name for any one of a class of substances, such as celluloid or viscose, which are worked into shape for use by molding or pressing when in a plastic condition