The underworld still makes solid profit out ofillicitliquor.

indigenous : originating or occurring naturally in a particular place; native.
illegitimate : not authorized by the law; not in accordance with accepted standards or rules.
illegal : contrary to or forbidden by law, especially criminal law.
country : a nation with its own government, occupying a particular territory.
illicit : forbidden by law, rules, or custom.
So, Synonym of illicit is illegal