mi·​cro·​plas·​tic | \ ˌmī-krō-ˈpla-stik How to pronounce microplastic (audio) \
plural microplastics

Definition of microplastic

: a very small fragment or piece of plastic specifically : a piece of plastic that is five millimeters or smaller in size usually plural Indeed, a handful of sand or cup of seawater from nearly anywhere in the world will probably be peppered with microplastics—pieces that are tinier than a small pea and often invisible. — Jennifer Ackerman… the Mariana Trench contains the highest levels of microplastics (most likely from clothing, bottles, packaging and fishing gear) yet found in the open ocean, offering irrefutable proof that plastics have penetrated even the most remote places on the planet. — Rina Li

Other Words from microplastic

microplastic adjective
microplastic pollution microplastic debris

First Known Use of microplastic

1990, in the meaning defined above

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The first known use of microplastic was in 1990

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Cite this Entry

“Microplastic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microplastic. Accessed 22 Sep. 2020.

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