1868, "appointed or nominated but not yet installed," past-participle adjective from designate (v.). The baseball designated hitter "substitute named before the start of a game to hit for the pitcher" was introduced in the American League in 1973; it soon gave wide figurative extension to designated, as in designated driver (by 1985).
late 14c., "gaping void; empty, immeasurable space," from Old French chaos (14c.) or directly from Latin chaos, from Greek khaos "abyss, that which gapes wide open, that which is vast and empty," from *khnwos, from PIE root *ghieh- "to yawn, gape, be wide open."
Meaning "utter confusion" (c. 1600) is an extended sense from theological use of chaos in the Vulgate version of "Genesis" (1530s in English) for "the void at the beginning of creation, the confused, formless, elementary state of the universe." The Greek for "disorder" was tarakhe, but the use of chaos here was rooted in Hesiod ("Theogony"), who describes khaos as the primeval emptiness of the Universe, and in Ovid ("Metamorphoses"), who opposes Khaos to Kosmos, "the ordered Universe." Sometimes it was personified as a god, begetter of Erebus and Nyx ("Night").
Meaning "orderless confusion" in human affairs is from c. 1600. Chaos theory in the modern mathematical sense is attested from c. 1977.
"coughing illness," a name given to various diseases involving interference at the glottis with respiration," 1765, from obsolete verb croup "to cry hoarsely, croak" (1510s), probably echoic. This was the local name of the disease in southeastern Scotland, given wide currency by Dr. Francis Home (1719-1813) of Edinburgh in his 1765 treatise on it. Related: Croupy.
also Athabascan, Athapaskan, 1844 as a language name, from the name of the widespread family of North American Indian languages, from Lake Athabaska in northern Alberta, Canada, from Woods Cree (Algonquian) Athapaskaw, literally "(where) there are plants one after another" [Bright], referring to the delta region west of the lake. The languages are spoken across a wide area of Alaska and sub-arctic Canada and include Apachean (including Navajo) in the U.S. southwest.