When you wander without a plan or a specific destination, you roam. Your cat may stay close to your house when you let her outside, or she may roam around the neighborhood all day.
Dogs and kids on bikes tend to roam in packs, looking for food or fun, while a tiger in the zoo roams aimlessly around his enclosure. Book characters' eyes sometimes roam, too, or glance over a scene without stopping: "Her eyes roam across the group, but there are no familiar faces." Experts have tried connecting roam to "pilgrimages to Rome," but there seems to be no relation between roam and Rome.