per- and polyfluoroalkyl substances
plural noun
variants
or less commonly perfluoroalkyl and polyfluoroalkyl substances
: synthetic chemicals that contain fluorinated carbon atoms, are used in consumer and industrial products for their desirable properties (such as water, stain, and fire resistance), are highly resistant to breakdown, and typically accumulate in soil and water as environmental pollutants : pfas
Per- and polyfluoroalkyl substances are industrial pollutants ubiquitously distributed that persist in the environment.—Andrea Rowan-Carroll et al.
PFAS, which stands for per- and polyfluoroalkyl substances, resist water, oil, heat, and grease. They've been used for decades in consumer products and industrial applications …—John Hilliard
Chemicals called PFAS, short for per- and polyfluoroalkyl substances, are sometimes called "forever chemicals" because they resist breaking down naturally in the environment, news reports said.—Julie Washington
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a class of synthetic chemicals widely used in coatings and foams that resist oil, heat and water. There are thousands of types of PFAS, used in everything from dental floss to waterproof jackets and non-stick pans.—Madeleine Cuff
—used in singular before another nounper- and polyfluoroalkyl substance toxicity
Cite this Entry
“Per- and polyfluoroalkyl substances.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/per-%20and%20polyfluoroalkyl%20substances. Accessed 15 Jul. 2026.
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