<p><strong>Noun</strong></p><ul><li>Practice of a pirate; robbery or illegal violence at sea.</li><li>The unauthorized reproduction or use of a copyrighted book, recording, television program, patented invention, trademarked product, etc.: The record industry is beset with piracy. Also called stream capture.</li><li>(Geology) Diversion of the upper part of one stream by the headward growth of another.</li></ul>