Adjective mercurial has 4 senses
- erratic, fickle, mercurial, quicksilver - liable to sudden unpredictable change; "erratic behavior"; "fickle weather"; "mercurial twists of temperament"; "a quicksilver character, cool and willful at one moment, utterly fragile the next"
Antonym: unchangeable (indirect, via changeable)
- Mercurial - relating to or under the (astrological) influence of the planet Mercury; "the Mercurial canals"
- Mercurial - relating to or having characteristics (eloquence, shrewdness, swiftness, thievishness) attributed to the god Mercury; "more than Mercurial thievishness"
- mercurial - relating to or containing or caused by mercury; "mercurial preparations"; "mercurial sore mouth"
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