naph·​thyl·​amine naf-ˈthi-lə-ˌmēn How to pronounce naphthylamine (audio)
 nonstandard  nap-
: either of two isomeric crystalline bases C10H9N used especially as dye intermediates

Word History


International Scientific Vocabulary

First Known Use

1857, in the meaning defined above

Time Traveler
The first known use of naphthylamine was in 1857

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Cite this Entry

“Naphthylamine.” Dictionary, Merriam-Webster, Accessed 30 Jan. 2023.

Medical Definition


naph·​thyl·​amine naf-ˈthil-ə-ˌmēn, nap- How to pronounce naphthylamine (audio)
: either of two isomeric crystalline bases C10H9N that are used especially in synthesizing dyes
especially : one (β–naphthylamine) with the amino group in the beta position that has been demonstrated to cause bladder cancer in individuals exposed to it while working in the dye industry

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