Vocabulary in context
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Mercurial
Describing a person whose mood or opinions shift quickly and unpredictably.
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Imagine This
Picture a coworker who shifts from sunny to irritable to exuberant all within minutes, as if guided by Mercury's rapid mood changes.
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Sounds Like
mer-KYOOR-ee-uhl
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Looks Like
Mercury (the swift Roman god and the planet) to suggest speed and change
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Remember This
Origin: from Latin mercuriālis 'of Mercury' — Mercury the swift messenger god; the sense captures speed, adaptability, and changeability.
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Other Forms
mercurialitynoun
mercuriallyadverb
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Connect With
volatile, capricious, fickle, erratic, temperamental
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Note
Common pitfall: mercurial describes mood or behavior that changes unpredictably, not necessarily intelligence or skill. Also distinguish from references to the metal mercury; the word here denotes changeability, not the substance itself.
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Study Deeper
Examples
- Her mercurial temperament made it hard to predict how she would react to criticism.
- The CEO's mercurial decisions left employees unsure of which plan would be adopted tomorrow.
Synonyms
ficklecapriciousvolatileerratictemperamental
Antonyms
stablepredictablesteady
Etymology
From Latin mercuriālis 'of Mercury,' from Mercury, the swift Roman messenger god; the sense conveys speed, changeability, and adaptability.
Mnemonic
Mercury-like mood changes: think of a quicksilver messenger who can turn on a dime.
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Lucrative
adjectiveProducing wealth; financially rewarding; yielding a great deal of profit.
Inadequate
adjectiveLacking the necessary quality, quantity, or ability to meet a purpose; not sufficient or suitable.
Finesse
noun and verbNoun: refined skill, tact, or diplomacy in handling a situation; Verb: to handle or achieve something with such skill or by clever, delicate maneuvering.
Similar Words
Related words and words with the same part of speech.
Capricious
adjectiveUnpredictable; given to sudden, unaccountable changes in mood or behavior.
Fickle
adjectiveOften changing; unstable or inconsistent in behavior, opinions, or loyalties.
Erratic
adjectiveNot regular or predictable; characterized by inconsistency or uncertainty.
Abstruse
adjectiveDifficult to understand; obscure or highly complex.
Accidental
adjectiveHappening by chance or without deliberate planning; not intended. In music, it is also a noun for a symbol that temporarily alters a pitch.
Acerbic
adjectiveSharp or biting in tone or taste; caustic or mordant in manner.
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