What does "mercurial" mean?
Any of the plants known as mercury, especially the annual mercury or French mercury (Mercurialis annua).
Mercurial
/məːˈkjʊə.ɹɪ.əl/ adj, noun
adj, noun ·Common ·High school level
Meaning at a glance
- Primary sense: Any of the plants known as mercury, especially the annual mercury or French mercury (Mercurialis annua).
- Grammar: mercurial is listed as adj, noun.
- Nearest alternatives: erratic, fickle, active, activist.
- Useful contrasts: constant, even-tempered, nonmercurial.
- Usage evidence: After the mercurial and embattled state governor left a profanity-laced message on a legislator's telephone answering machine, he tried to explain himself: "I was so angry that I couldn't breathe."
How to use "mercurial"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "mercurial" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
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- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "mercurial" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
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Compare nearby meanings
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Definition decision workflow
1. Identify the role
Check whether "mercurial" is acting as adj, noun in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
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3. Confirm with context
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Final meaning check
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Definitions
Noun
- 1 Any of the plants known as mercury, especially the annual mercury or French mercury (Mercurialis annua). obsolete
- 2 A person born under the influence of the planet Mercury; hence, a person having an eloquent, quickwitted, furtive, or volatile character.
"As for [Lambert] Simnell, there was not much in him, more then that hee was a handſome Boy, and did not ſhame his Robes. But this Youth (of whom wee are now to ſpeake) was ſuch a Mercuriall, as the like hath ſeldome beene knowne; and could make his owne part, if at any time hee chanced to bee out."
- 3 A chemical compound containing mercury.
- 4 A preparation of mercury, especially as a treatment for syphilis. historical
"She had paſſed through the milder Remedies frequently without ſucceſs: upon which account I deſigned Mercurialls; and beginning with Venæſection, afterwards purged her with decoct. epithymi, as it is preſcribed in the method of Cure. [...] After I had thus evacuated the Plethora, and diſpoſed her body for Mercurialls more operative, I gave her each morning and evening a few grains of Mercur. diaphoret. in a bolus with conſ. lujule and Mithridate, [...]"
Adjective
- 1 Having a lively or volatile character; animated, changeable, quick-witted. comparable
"his mercurial temperament"
- 2 Alternative letter-case form of mercurial. alt-of
"He firſt ſubſiſts in Jupiter, the artificer of the world; next, among the ſupermundane gods; in the third place, among the liberated gods; fourthly, in the planet Mercury; fifthly, in the Mercurial order of demons; […] Likewiſe in this city a certain man once flouriſhed, full of the Mercurial power, becauſe his ſoul formerly exiſted in the heavens of the Mercurial order. […] But afterwards a demon, becauſe from the god Mercury, through a Mercurial demon, gifts of this kind are tranſmitted to a Mercurial ſoul."
- 3 Pertaining to the astrological influence of the planet Mercury; having the characteristics of a person under such influence (see adjective sense 1). not-comparable
"The Sun to the Terms of Mercury. It inclineth the native to be Mercurial, given to ſtudy Arts and Sciences, and to delight in reading, and to follow his Calling with chearfulneſs."
- 4 Pertaining to the planet Mercury. not-comparable
- 5 Of or pertaining to the element mercury or quicksilver; containing mercury. not-comparable
"Beware alſo of Mercuriall lotions, I meane any which haue Mercurie Sublimate Precipitat or otherwiſe prepared in them, for though they haue good qualities, yet they are vpon my knowledge and experience dangerous, [...]"
Show 2 more definitions
- 6 Caused by the action of mercury or a mercury compound. not-comparable
"I ſaw in the Year 1709. a notable inſtance, where a Phyſician order'd the Patient to be Bled five times in a Mercurial Salivation in a Caſe not Venereal; when he did ſpit at the rate of ℔ iv. per diem, and it was at the height, and yet notwithſtanding it did continue for all this, and the Patient eſcap'd with his Life."
- 7 Pertaining to Mercury, the Roman god of, among other things, commerce, financial gain, communication, and thieves and trickery; hence (comparable), money-making; crafty. Roman, not-comparable
"Near-synonym: Hermesian"
Adjective
- 1 liable to sudden unpredictable change wordnet
- 2 relating to or containing or caused by mercury wordnet
- 3 relating to or having characteristics (eloquence, shrewdness, swiftness, thievishness) attributed to the god Mercury wordnet
- 4 relating to or under the (astrological) influence of the planet Mercury wordnet
Example
"After the mercurial and embattled state governor left a profanity-laced message on a legislator's telephone answering machine, he tried to explain himself: "I was so angry that I couldn't breathe.""
Common questions
What is a synonym for "mercurial"?
Common synonyms include: erratic, fickle, active, activist, activistic, adrift.
How do you use "mercurial" in a sentence?
After the mercurial and embattled state governor left a profanity-laced message on a legislator's telephone answering machine, he tried to explain himself: "I was so angry that I couldn't breathe."
How do you pronounce "mercurial"?
Pronounced /məːˈkjʊə.ɹɪ.əl/.
Etymology
Noun sense 1 (“(obsolete) plant known as mercury”) is from Middle English mercurial, from Anglo-Norman mercurial and Old French mercurial, or directly from their etymon, from Mercurius (“the Roman god Mercury”) + -ālis (suffix forming adjectives of relationship from nouns). Later adjective and noun uses may have been directly derived from Latin mercuriālis, whence Middle English mercurial (“under the astrological influence of the planet Mercury”).