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Showing results for mercurial. Search instead for cercarial.
Definitions

mercurial

[mer-kyoor-ee-uhl] / mərˈkyʊər i əl /
ADJECTIVE
flighty, temperamental
Synonyms
STRONGEST
changeable effervescent erratic impulsive resilient unpredictable volatile
WEAK
blowing hot and cold bubbleheaded buoyant capricious elastic expansive fickle flaky flip fluctuating gaga gay inconstant irregular irrepressible lighthearted lively lubricious mad mobile movable quicksilver spirited sprightly ticklish unstable up-and-down variable yo-yo
Antonyms
STRONGEST
certain constant predictable reliable stable steady sure unchanging
WEAK
calm tranquil unchangeable unperturbable unvarying

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Master of the trivela, lover of a rabona - mercurial and erratic, but show-stoppingly skilful.

From BBC • Mar. 24, 2026

In recent years, the mercurial superstar has faced a number of public and legal dramas.

From Los Angeles Times • Mar. 11, 2026

Still, China is treading carefully because one of the biggest calculations for them is the mercurial US president, who is due to arrive for a much-awaited meeting later this month.

From BBC • Mar. 5, 2026

Capital Group ascended to the No. 1 spot by taking advantage of mercurial markets and seeing long-term bets pay off.

From Barron's • Feb. 26, 2026

“Once in a while Lainie suggests that we follow it around ourselves but I think that would only be a temporary solution, we are too mercurial for our own good.”

From "The Night Circus" by Erin Morgenstern

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.