From Longman Dictionary of Contemporary Englishtravelling companiontravelling companionsomeone you are on a journey with → travelling
Examples from the Corpus
travelling companion• A lot has to do with one's travelling companion.• Blake sighed, and ran to catch up with his travelling companion.• Indeed, I worship the little devil, but only as a travelling companion.• Sad for the bulk of his travelling companions; glad that his own destiny was different.• Her travelling companions had quietened, as if some one in authority had arrived.• My other travelling companion, John Lawrence, would describe himself first and foremost as a writer.• In the back of the taxi, our two temporary travelling companions sit as far apart as possible.• Thesiger invited him and his travelling companion to spend the night with his caravan. 