dormant volcano in Tanzania, it is the highest mountain in Africa. The name is of unknown origin; the first element appears to be Swahili kilima "(little) mountain," but even this is uncertain. See J.A. Hutchinson, "The Meaning of Kilimanjaro," in Tanganyika Notes and Records, 1965.
"cavity on the summit of a volcano," 1865, from Spanish caldera, literally "cauldron, kettle," from Latin caldarium "hot-bath" (plural caldaria), from caldarius "pertaining to warming," from calidus "warm, hot" (from PIE root *kele- (1) "warm"). A doublet of cauldron.
The term was originally used in describing volcanic regions occurring where Spanish is the current language, and was introduced by Von Buch in his description of the Canaries. [Century Dictionary]
As a noun, it is recorded from 1809 in the sense "outburst, quarrel;" 1807 as "an explosion." Meaning "enlargement from a photograph" is attested by 1945 (the verbal phrase in this sense is by 1930). Old English had an adjective upablawan "upblown," used of a volcano, etc.