mi·​cro·​plas·​tic ˌmī-krō-ˈpla-stik How to pronounce microplastic (audio)
plural microplastics
: 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
microplastic adjective
microplastic pollution
microplastic debris

Word History

First Known Use

1990, in the meaning defined above

Time Traveler
The first known use of microplastic was in 1990

Dictionary Entries Near microplastic

Cite this Entry

“Microplastic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microplastic. Accessed 6 Dec. 2022.

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