combining form
variants: or


less commonly


Definition of naphth-

  1. 1 :  naphtha naphthene naphthyl

  2. 2a :  related to naphthalene :  naphthoic acid naphthoquinone naphthamide —sometimes in names of compounds in which a benzene nucleus has been replaced by a naphthalene nucleus naphthoresorcinol C10H6(OH)2 b :  naphthol naphthoxide

  3. 3a :  containing a naphthalene nucleus fused on one or two sides to one or two other rings naphthacridine naphthopyran naphthadiazine b :  benz- 2 —not used systematically naphthanthracene

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Origin and Etymology of naphth-

International Scientific Vocabulary, from naphtha & naphthaline

Seen and Heard

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a trip made at another's expense

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