polyester

American  

[pol-ee-es-ter, pol-ee-es-ter] / ˈpɒl iˌɛs tər, ˌpɒl iˈɛs tər /

noun

1. Chemistry. a polymer in which the monomer units are linked together by the group –COO–, usually formed by polymerizing a polyhydric alcohol with a polybasic acid: used chiefly in the manufacture of resins, plastics, and textile fibers.

2. Also called poly.  a fabric made from such textile fibers.

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polyester British  

/ ˌpɒlɪˈɛstə /

noun

1. any of a large class of synthetic materials that are polymers containing recurring -COO- groups: used as plastics, textile fibres, and adhesives

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polyester Scientific  

/ pŏl′ē-ĕs′tər /

1. Any of various mostly synthetic polymers that are light, strong resins resistant to weather and corrosion. Polyesters are long chains of esters and are used to make fibers and plastics. They are thermosetting. Some polyesters, such as suberin, occur naturally.

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Other Word Forms

• polyesterification noun

Etymology

Origin of polyester

First recorded in 1925–30; poly- + ester

Example Sentences

Similarly, the polyester film in those shiny foil party balloons is also made from crude oil.

From The Wall Street Journal • Mar. 21, 2026

It is hard to get dressed without encountering oil-based products, which are woven into modern clothing in the form of polyester, nylon, acrylic and other synthetic fibers.

From The Wall Street Journal • Mar. 21, 2026

The swish of polyester skirts in spring pastels — lavender, mint, butter-yellow — as the women of the church organized the spread.

From Salon • Mar. 15, 2026

These clothes are made with blends of cotton and polyester that are hard to break down, and thus end up in legal—or sometimes illegal—landfills with their own environmental hazards.

From Slate • Jan. 26, 2026

She had a man's necktie wrapped around her ponytail like a big polyester ribbon.

From "Eleanor & Park" by Rainbow Rowell