What is Piratical?

Piratical definition and meaning on Dictionary terms:
a person who robs or commits illegal violence at sea or on the shores of the sea.
a ship used by such persons.
any plunderer, predator, etc.: confidence men, slumlords, and other pirates.

a person who uses or reproduces the work or invention of another without authorization.
Also called pirate stream. Geology. a stream that diverts into its own flow the headwaters of another stream, river, etc.

verb (used with object), pi