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.

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

From Los Angeles Times • Mar. 11, 2026

Mr. McCallum’s sharp alliterations and choice of words transform a book review into a wonderful exploration of a mercurial star.

From The Wall Street Journal • Mar. 2, 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

Fourth was the mercurial Arwel Thomas, who was the star man for Swansea and whom Henson tried to learn off when starting out as a young player.

From BBC • Feb. 21, 2026

Her personality was too big and mercurial to be contained in a frail human body.

From "Darius the Great Is Not Okay" by Adib Khorram

Vocabulary lists containing mercurial

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