Webster's Revised Unabridged Dictionary · 1913

Terephthalic

Terephthalic , adjective

[Terebene + phthalic.]

(Chemistry) Of, pertaining to, or designating, a dibasic acid of the aromatic series, metameric with phthalic acid, and obtained, as a tasteless white crystalline powder, by the oxidation of oil of turpentine; -- called also paraphthalic acid. Compare Phthalic.