Someone who climbs mountains.

synonym: mountain climber.

Roget 268: traveler, wayfarer, voyager, itinerant, passenger, commuter.    tourist, excursionist, explorer, adventurer, mountaineer, hiker, backpacker, Alpine Club; peregrinator^†, wanderer, rover, straggler, rambler; bird of passage; gadabout, gadling^†; vagrant, scatterling^†, landloper^†, waifs and estrays^†, wastrel, foundling; loafer; tramp, tramper; vagabond, nomad, Bohemian, gypsy, Arab^†, Wandering Jew, Hadji, pilgrim, palmer; peripatetic; somnambulist, emigrant, fugitive, refugee; beach comber, booly^†; globegirdler^†, globetrotter; vagrant, hobo [U.S.], night walker, sleep walker; noctambulist, runabout, straphanger, swagman, swagsman [Austral.]; trecker^†, trekker, zingano^†, zingaro^†.    runner, courier; Mercury, Iris, Ariel^†, comet.    pedestrian, walker, foot passenger; cyclist; wheelman.    rider, horseman, equestrian, cavalier, jockey, roughrider, trainer, breaker.    driver, coachman, whip, Jehu, charioteer, postilion, postboy^†, carter, wagoner, drayman^†; cabman, cabdriver; voiturier^†, vetturino^†, condottiere^†; engine driver; stoker, fireman, guard; chauffeur, conductor, engineer, gharry-wallah^†, gari-wala^†, hackman, syce^†, truckman^†.    ... show more

Dutch: alpinist, bergbeklimmer, kletteraar, klimmer
Polish: górołaz

Climb mountains for pleasure as a sport.

Dutch: bergbeklimmen, kletteren