phthalic anhydride

noun

: a crystalline cyclic acid anhydride C₈H₄O₃ used especially in making alkyd resins

Word History

First Known Use

1855, in the meaning defined above

Time Traveler

The first known use of phthalic anhydride was in 1855

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phthalic acid

phthalic anhydride

phthalide

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“Phthalic anhydride.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phthalic%20anhydride. Accessed 26 Jul. 2025.

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Medical Definition

phthalic anhydride

noun

: a crystalline cyclic acid anhydride C₈H₄O₃ that is used especially in making alkyd resins and is a structural part of thalidomide

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phthalic anhydride

noun

Word History

Browse Nearby Words

Cite this Entry

Medical Definition

More from Merriam-Webster on phthalic anhydride