Simple Definition of mercurial
: changing moods quickly and often
: changing often : very changeable
: very lively and quick
Full Definition of mercurial
1 : of, relating to, or born under the planet Mercury
2 : having qualities of eloquence, ingenuity, or thievishness attributed to the god Mercury or to the influence of the planet Mercury
3 : characterized by rapid and unpredictable changeableness of mood <a mercurial temper>
4 : of, relating to, containing, or caused by mercury
Examples of mercurial in a sentence
Few moments in English history have been more hungry for the future, its mercurial possibilities and its hope of richness, than the spring of 1603. —Adam Nicolson, God's Secretaries, 2003
Though you could see all three places in one day, each of them makes you want to stay or to keep returning to watch the effects of the changing weather and the mercurial Sicilian light. —Francine Prose, Atlantic, December 2002
Some scientists suggest that because manic-depressive patients are ever riding the bio-chemical express between emotional extremes, their brains end up more complexly wired and remain more persistently plastic than do the brains of less mercurial sorts. —Natalie Angier, New York Times, 12 Oct. 1993
Still grinning, still miming, he samba-ed across the floor … and started in on the dishes with a vigor that would have prostrated his mercurial cousin. —T. Coraghessan Boyle, Harper's, October 1987
<the boss's mood is so mercurial that we never know how he's going to react to anything>
Did You Know?
The Roman god Mercury ("Mercurius" in Latin) was the messenger and herald of the gods and also the god of merchants and thieves. (His counterpart in Greek mythology is Hermes.) He was noted for his eloquence, swiftness, and cunning, and the Romans named what appeared to them to be the fastest-moving planet in his honor. The Latin adjective derived from his name, mercurialis, meaning "of or relating to Mercury," was borrowed into English in the 14th century as "mercurial." Although the adjective initially meant "born under the planet Mercury," it came to mean also "having qualities of eloquence, ingenuity, or thievishness attributed to the god Mercury or the influence of the planet Mercury," and then "unpredictably changeable."
Origin of mercurial
First Known Use: 14th century
Synonym Discussion of mercurial
Origin of mercurial
First Known Use: 1676
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