traveller vs fellow traveller

Other hyponyms of traveller include absentee, air traveler, air traveller, arrival, arriver, comer, astronaut, cosmonaut, spaceman, business traveler, bearer, carrier, toter, companion, fellow traveler, entrant, flier, flyer, follower, alien, foreigner, noncitizen, outlander, hosteller, courier, messenger, migrant, migrator, motorcyclist, mover, musher, passenger, rider, footer, pedestrian, walker, rafter, raftman, raftsman, rider, rider, runner, scourer, bather, natator, swimmer, holidaymaker, tourer, tourist, transient, trekker, visitant, visitor, voyager, bird of passage, roamer, rover, wanderer, journeyer, wayfarer.