Origin: bef. 1000; ME
climben, OE
climban; c. D, G
klimmen; akin to
clamber 
Related forms: climb⋅a⋅ble, adjective
Synonyms:
8. Climb, ascend, mount, scale imply a moving upward. To climb is to make one's way upward, often with effort: to climb a mountain. Ascend, in its literal meaning (“to go up”), is general, but it now usually suggests a gradual or stately movement, with or without effort, often to a considerable degree of altitude: to ascend the heights; to ascend the Himalayas. Mount may be interchangeable with ascend, but also suggests climbing on top of or astride of: to mount a platform, a horse. Scale, a more literary word, implies difficult or hazardous climbing up or over something: to scale a summit.
Antonyms:
1, 8. descend. 10. descent.