[‚ak·rə‚lō′nī·trəl ‚byüd·ə′dī‚ēn ′stī·rēn ′rez·ən] (organic chemistry) A polymer made by blending acrylonitrile-styrene copolymer with a butadiene-acrylonitrile rubber or by interpolymerizing polybutadiene with styrene and acrylonitrile; combines the advantages of hardness and strength of the vinyl resin component with the toughness and impact resistance of the rubbery component. Abbreviated ABS.