Webster's Revised Unabridged Dictionary · 1913

Ichthyol

Ichthyol , noun

[Greek 'ichqy`s, -y`os, a fish + (prob.) Latin oleum oil; but compare Ichthyolite.]

(Chemistry) An oily substance prepared by the dry distillation of a bituminous mineral containing fossil fishes. It is used in medicine as a remedy in some forms of skin diseases.