the GNU version of the Collaborative International Dictionary of English
verb-intransitive. To make a raid for booty; to maraud; also, to skirmish in advance of an army. See picaroon.
The Century Dictionary and Cyclopedia
To serve in irregular or skirmishing warfare; form part of a body of skirmishers acting in the front or on the wings of an army, or independently, as foragers, etc.; act as a skirmisher.