Privateer
From WikiPOBia
An armed vessel not belonging to a national navy, but given permission by a belligerent nation to engage in war on its behalf. The government of the nation would provide the captain of the privateer with a document called a Letter of Marque and Reprisal.
In practice, privateers would primarily attack merchant vessels from the enemy countries, avoiding naval vessels if possible. The owners of the privateers would profit from the sale of the captured vessels.
Essentially, privateers were legalized pirates (and had in earlier eras degenerated into true piracy). For this reason, officers disliked the term, preferring the more formal Letter of Marque.
