mountaineering

As a noun mountaineering

is (senseid) the sport of climbing mountains.

As a letter x is

the twenty-fourth letter of the.

As a symbol x is

voiceless velar fricative.

As nouns the difference between mountaineering and alpinism

is that mountaineering is (sport) the sport of climbing mountains while alpinism is mountain climbing, especially in the Alps.

As nouns the difference between albinism and mountaineering

is that albinism is congenital lack of melanin pigmentation in the skin, eyes, and hair or feathers (or more rarely only in the eyes); the condition of being albino while mountaineering is (senseid) the sport of climbing mountains.

As nouns the difference between taxonomy and mountaineering

is that taxonomy is the science or the technique used to make a classification while mountaineering is (sport) the sport of climbing mountains.

As nouns the difference between mountaineering and scale

is that mountaineering is (senseid) the sport of climbing mountains while scale is (obsolete) a ladder; a series of steps; a means of ascending or scale can be part of an overlapping arrangement of many small, flat and hard pieces of keratin covering the skin of an animal, particularly a fish or reptile or scale can be a device to measure mass or weight.

As a verb scale is

to change the size of something whilst maintaining proportion; especially to change a process in order to produce much larger amounts of the final product or scale can be to remove the scales of.