combining form
variants: or naphtho- or less commonly naphtha-

Definition of naphth-

1 : naphtha naphthene naphthyl
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naphthalene : naphthoic acid naphthoquinone naphthamide sometimes in names of compounds in which a benzene nucleus has been replaced by a naphthalene nucleus naphthoresorcinol C10H6(OH)2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
3a : containing a naphthalene nucleus fused on one or two sides to one or two other rings naphthacridine naphthopyran naphthadiazine
b : benz- sense 2 not used systematically naphthanthracene

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History and Etymology for naphth-

International Scientific Vocabulary, from naphtha & naphthaline

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to wander slowly or to speak indistinctly

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