quicksilver

Etymology

From Middle English quyk silver, quyksilver, quikselver, from Old English cwicseolfor (“quicksilver”, literally “living silver”) (see Latin argentum vivum) from its ability to move. See quick in the sense of "living". Equivalent to quick + silver. Cognate with Dutch kwikzilver, German Low German Quicksülver, German Quecksilber, Danish kviksølv, Norwegian Bokmål kvikksølv, Swedish kvicksilver.

noun

1. The metal mercury.
2. (colloquial) An amalgam of mercury and tin applied to the backs of mirrors, quicksilvering.

adj

1. Unpredictable, erratic or fickle; mercurial.
   The idea of a merchant selling both totems of pure evil and frozen yogurt (he calls it frogurt!) is amusing in itself, as is the idea that frogurt could be cursed, but it’s really the Shopkeeper’s quicksilver shift from ominous doomsaying to chipper salesmanship that sells the sequence. April 29, 2012, Nathan Rabin, “TV: Review: THE SIMPSONS (CLASSIC): “Treehouse of Horror III” (season 4, episode 5; originally aired 10/29/1992)”, in (Please provide the book title or journal name)

verb

1. To overlay with quicksilver.
2. To treat with quicksilver.