Emily Dickinson Lexicon

PA-TROL', or PA-TROLL', n. [Fr. patrouille; Sp. patrulla; Port. patrulha. See the verb.]

1. In war, a round; a walking or marching round by a guard in the night, to watch and observe what passes, and to secure the peace and safety of a camp or other place.
2. The guard or persons who go the rounds for observation a detachment whose duty is to patrol. In France, there is an army of patrols to secure her fiscal regulations. – Hamilton.