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Synonyms

mercurial

American  
[mer-kyoor-ee-uhl] / mərˈkyʊər i əl /

adjective

  1. changeable; volatile; fickle; flighty; erratic.

    a mercurial nature.

    Synonyms:
    indecisive, inconstant
    Antonyms:
    steady, constant
  2. animated; lively; sprightly; quick-witted.

    Synonyms:
    spirited
    Antonyms:
    phlegmatic
  3. pertaining to, containing, or caused by the metal mercury.

  4. (initial capital letter) of or relating to the god Mercury.

  5. (initial capital letter) of or relating to the planet Mercury.


noun

  1. Pharmacology. a preparation of mercury used as a drug.

mercurial British  
/ mɜːˈkjʊərɪəl /

adjective

  1. of, like, containing, or relating to mercury

  2. volatile; lively

    a mercurial temperament

  3. (sometimes capital) of, like, or relating to the god or the planet Mercury

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. med any salt of mercury for use as a medicine

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • mercuriality noun
  • mercurially adverb
  • mercurialness noun
  • unmercurial adjective
  • unmercurially adverb
  • unmercurialness noun

Etymology

Origin of mercurial

First recorded in 1350–1400; Middle English, from Latin mercuriālis “of or pertaining to the god or planet Mercury”; mercury, -al 1

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.

Legxacy is a mercurial figure – a musical polymath, defiantly original, who has largely stopped speaking in public, partly due to the tragic backstory behind his latest mixtape.

From BBC

Sabalenka said the fact that she played so well in her first match of the season showed that the December 28 exhibition in Dubai against the mercurial but controversial Kyrgios was worthwhile.

From Barron's

His mercurial talent would be nurtured by the 1986 World Champion Joe Johnson, from neighbouring Bradford, at a now defunct club in the north Leeds suburb of Yeadon, a few miles from their home.

From BBC

It is, however, for his brilliance under the guidance of the mercurial Clough at the City Ground for which the winger team-mates described as "pure genius" will always be remembered.

From BBC

Bettors were backing the mercurial and less experienced Paul with hopes for a big payday — dreams that were crushed when Joshua beat Paul handily.

From MarketWatch