• (n.) 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.
Ich'thy·ol noun [ Greek ..., ..., a fish + (prob.) Latin ol eum oil; but confer 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. 
a brand of ichthammol.