(1):

(a.) Having the power to give form or fashion to a mass of matter; as, the plastic hand of the Creator.

(2):

(a.) Capable of being molded, formed, or modeled, as clay or plaster; - used also figuratively; as, the plastic mind of a child.

(3):

(a.) Pertaining or appropriate to, or characteristic of, molding or modeling; produced by, or appearing as if produced by, molding or modeling; - said of sculpture and the kindred arts, in distinction from painting and the graphic arts.