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Webster 1913 Edition

Adj.

[Na

phthal

ene +

-ic

(Chem.)

Pertaining to, or designating, a dibasic acid obtained by the oxidation of naphthalene and allied substances.

Phthalic acid

(Chem.)

a white crystalline substance,

C6H4.(CO2H)2

, analogous to benzoic acid, and employed in the brilliant dyestuffs called the phthaleins.

phthalic ‎(not comparable)

of or relating to naphthalene or phthalic acid