Definition of "Plastic" :

noun: a card (usually plastic) that assures a seller that the person using it has a satisfactory credit rating and that the issuer will see to it that the seller receives payment for the merchandise delivered

"Do you take plastic?."

noun: generic name for certain synthetic or semisynthetic materials that can be molded or extruded into objects or films or filaments or used for making e.g. coatings and adhesives

adjective: forming or capable of forming or molding or fashioning

"The plastic forces of nature."

adjective: capable of being molded or modeled (especially of earth or clay or other soft material)

"Plastic substances such as wax or clay."

adjective: capable of being influenced or formed

"The plastic minds of children."