: a secondary treatment to which a material (as film or dyed goods) is subjected after the primary treatment is finished

Word History


after- + treatment

First Known Use

1852, in the meaning defined above

Time Traveler
The first known use of aftertreatment was in 1852

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Dictionary Entries Near aftertreatment

Cite this Entry

“Aftertreatment.” Dictionary, Merriam-Webster, Accessed 5 Dec. 2023.

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