1650s, member of Tungusic race of Manchuria which conquered China in 1644 and remained its ruling class until the Revolution of 1912. From a native word in the Manchu language meaning literally "pure," used as the name of the tribe descended from the Nu-chen Tartars.
inert gaseous element, 1898, coined by its discoverers (Sir William Ramsay and Morris W. Travers) from Greek krypton, neuter of adjective kryptos "hidden" (see crypt); so called because it remained undiscovered for so long and was so difficult to find. Scientific American (July 9, 1898) announced it as "the discovery of yet another element."
type of copper penny, 1839, American English, from red (adj.1) + cent. Pure copper pennies were issued 1793–1857, then replaced by ones of copper-nickel and, after 1864, bronze. The old cents were disused, but the phrase remained colloquial as a mere emphatic of cent, usually in the negative (don't have a ... not worth a ...). "Red" has been the color of copper, brass, and gold since ancient times.
c. 1300, mencioun, "a note, a reference, a calling to mind by speech or writing," from Old French mencion "mention, memory, speech," from Latin mentionem (nominative mentio) "a calling to mind, a speaking of, a making mention," from root of Old Latin minisci "to think," related to mens (genitive mentis) "mind," from PIE root *men- (1) "to think." From late 15c. as "statement about or in reference to a person or thing," which by mid-18c. had diminished to "incidental or casual reference," though in military use a mention in the dispatches remained an important thing.
1630s, in Greek mythology, the name of the first mortal woman, made by Hephaestus and given as a bride to Epimetheus, from Greek Pandōra "all-gifted" (or perhaps "giver of all"), from pan- "all" (see pan-) + dōron "gift" (from PIE root *do- "to give").
Pandora's box (1570s) refers to her gift from Zeus, which was foolishly opened by Epimetheus, upon which all the contents escaped. They were said to be the host of human ills (escaping to afflict mankind), or, in a later version, all the blessings of the god (escaping to be lost), except Hope, which alone remained.
The noun was borrowed earlier (c. 1400) from Old French in a sense "(someone's) control;" and compare Middle English adverbial phrase at abandon, i.e. "recklessly," attested from late 14c. In Old French, the past-participle adjective abandoné came to mean "zealous, eager, unreserved."