plural -s
: a colorless liquid diketone of pleasant odor known in two forms [keto form CH3COCH2COCH3 and enol form CH3COCHC(OH)CH3] made in various ways (as by the reaction of sodium with acetone and ethyl acetate); 2,4-pentanedione

Word History


International Scientific Vocabulary acetyl + acetone

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of acetylacetone was in 1887

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Dictionary Entries Near acetylacetone

Cite this Entry

“Acetylacetone.” Dictionary, Merriam-Webster, Accessed 20 Jun. 2024.

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