Use the noun quicksilver when you need a more poetic way to talk about the element known as mercury. If you look closely at an old-fashioned thermometer, you can see the quicksilver inside it.

It's more common to refer to this metal — the only one that is liquid at room temperature — as mercury, but it's also correct to call it quicksilver, which describes the properties of the element very well. Quicksilver is liquid, silver colored, and is fascinating to look at. The word comes from the sense of quick that means "alive;" the Latin root is argentum vivum, which is literally "living silver."

Definitions of quicksilver

n a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures

Hg, atomic number 80, hydrargyrum, mercury
Type of:
metal, metallic element
any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.

adj liable to sudden unpredictable change

“a quicksilver character, cool and willful at one moment, utterly fragile the next”
erratic, fickle, mercurial
changeable, changeful
such that alteration is possible; having a marked tendency to change

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.