What is pertaining to, derived from, or related to, xylene; specifically, designating any one of several metameric acids produced by the partial oxidation of mesitylene and pseudo-cumene called?

xylic — Pertaining to, derived from, or related to, xylene; specifically, designating any one of several metameric acids produced by the partial oxidation of mesitylene and pseudo-cumene. (Webster's 1913.)

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