In the 18th century, many merchant ships were authorized to privateer against enemy vessels.

privateer 是由 private（私人的）加上后缀 -eer（表示"从事...的人"）构成的名词，指"私掠船"或"私掠船船员"。这个词特指获得政府授权可以合法攻击敌国商船的私人武装船只。