pol·y·es·ter 
(pŏlē-ĕs′tər, pŏl′ē-ĕstər)
(pŏlē-ĕs′tər, pŏl′ē-ĕstər)n.
1. Any of numerous synthetic polymers produced chiefly by reaction of dicarboxylic acids with dihydric alcohols and used primarily as light, strong, weather-resistant resins in boat hulls, textile fibers, adhesives, and molded parts.
2. A wrinkle-resistant fabric of fibers made from any of these resins.
poly·es′ter adj.
pol′y·es′ter·i·fi·cation (-ə-fĭ-kāshən) n.