mercurial

adjective mer·cu·ri·al \ (ˌ)mər-ˈkyu̇r-ē-əl \

Updated on: 21 Apr 2018

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

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mercurially

play \-ē-ə-lē\ adverb

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mercurialness

noun

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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

Recent Examples of mercurial from the Web

As if things couldn't get any worse for West Brom, United's mercurial attacking midfielder Paul Pogba will go into Sunday's match on a high, after his devastating display at the Etihad last weekend.

— SI.com, "Manchester United vs West Bromwich Albion Preview: Recent Form, Key Battles, Team News & More," 14 Apr. 2018
And then there's DeMarcus Cousins, the mercurial and uber-talented big man who averaged 33.6 points and 13.3 rebounds in three games against Portland this season before suffering a season-ending Achilles injury in late January.

— andrew greif, OregonLive.com, "Trail Blazers look ahead to Pelicans in playoffs: 'Everything starts with Anthony Davis'," 12 Apr. 2018
Expression is everything to mercurial Gemini, and so their partnerships are fueled by communication.

— aliza kelly faragher, Allure, "How Each Zodiac Sign Handles a Breakup," 11 Apr. 2018
All of this is happening in the wake of key departures of Trump staff who have been seen as stabilizing influences on the mercurial president.

— brian bennett, Time, "Why Tuesday Could Define Trump's Presidency," 10 Apr. 2018
Tillerson frequently complained to colleagues that Trump was too mercurial and impulsive, and voiced frustration that the president struggled to focus during meandering conversation.

— philip rucker, Washington Post, "‘It was a different mind-set’: How Trump soured on Tillerson as his top diplomat," 13 Mar. 2018
New coach Jon Gruden has made moves to clean up the locker room—whacking Michael Crabtree was one—but leaving Lynch there means bringing back a player who was mercurial, inconsistent and never seemed to fully buy into Jack Del Rio’s program.

— albert breer, SI.com, "Rainy Pro Day Does Nothing to Dampen Enthusiasm for Sam Darnold as Likely Top Draft Pick," 22 Mar. 2018
According to The New York Times, the departure stemmed from strategic differences between the prominent Washington defense attorney and his mercurial client.

— matt ford, The New Republic, "The Worst Job in Washington," 22 Mar. 2018
With the official start of spring less than a week away, and weather patterns skewing slightly toward mercurial, transitional looks are on everyone's minds—a fact made evident by an upswing in the body-confident showing of crop-top abs.

— calin van paris, Vogue, "Kendall Jenner, Cardi B, and More Show Why Crop-Top Abs—and Confidence— are a Perfect Match," 16 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mercurial.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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 and Etymology of mercurial

see mercury

NEW! Time Traveler

First Known Use: 14th century

in the meaning defined at sense 1

See Words from the same year

mercurial Synonyms

Phrases

up in the air;

Synonym Discussion of mercurial

inconstant, fickle, capricious, mercurial, unstable mean lacking firmness or steadiness (as in purpose or devotion). inconstant implies an incapacity for steadiness and an inherent tendency to change.