"pertaining to the people dwelling on the opposite side of the earth," 1860, from antoeci (plural) "people dwelling on the opposite side of the earth" (1620s), a Latinized form of Greek antoikoi, literally "dwellers opposite," from anti "opposite" (see anti-) + oikein "to dwell" (from PIE root *weik- (1) "clan").
"rock or metallic mass of extraterrestrial origin that falls to earth after streaking across the sky as a meteor," 1818, from meteor + -ite. They were known from ancient times, but the idea that some such iron masses or rocks had fallen to earth from the sky attained credence among scientists c. 1800.
1540s, "a tract or region of the earth," shortening of climate (or a nativization of Latin clima). It might usefully take up the old, abandoned "horizontal region of the earth" sense of climate, but it is used chiefly by the poets, and they display no evident agreement on what they mean by it.
element, obtained 1906 from an earth discovered in 1886, the last to be extracted from the complex earth called yttria, and named dysprosia in reference to the difficulty of obtaining it, from Greek dysprositos "hard to get at, difficult of access," from dys- "bad, difficult" (see dys-) + prositos "approachable." With metallic element suffix -ium.