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mercurial

[mer-kyoor-ee-uhl]

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May 28, 2026
mercurial

[mer-kyoor-ee-uhl]

adjective
volatile; fickle; erratic

Explanation
Someone described as mercurial tends to shift quickly from one mood or direction to another. The word descends directly from Mercury, the Roman messenger god known for his speed and unpredictability. That sense of quick change carries through today, keeping life full of surprises.

Example
His mercurial personality meant he was laughing with us one minute and arguing the next.

May 27, 2026
swivet

[swiv-it]

noun
a state of nervous excitement, haste, or anxiety

Explanation
A swivet is a heightened state of nervousness, the kind that sends you rushing or even spiraling, but often over something small. The word tends to show up in the phrase "in a swivet," and it has a playful sound that softens the feeling it describes. It's easy to find yourself in a swivet, so have a mental escape plan ready for when it happens.

Example
She was in a swivet trying to find the right pasta shape for the pasta salad she planned to bring to the potluck.

May 26, 2026
tarry

[tar-ee]

verb
to delay in coming or going; linger

Explanation
To tarry is to linger or delay when you might otherwise move on. Though less common in everyday speech now, the word still appeals to people who like its measured, nonjudgmental tone. Just remember that there's a difference between tarrying and procrastinating!

Example
Don't tarry too long at the library, or you will miss the bus home.

May 25, 2026
poignant

[poin-yuhnt]

adjective
affecting or moving the emotions

Explanation
Poignant describes something that deeply affects you emotionally, sometimes with a dash of bittersweetness thrown in. It traces back to a Latin word meaning "to prick," the same root that gives us "puncture." This linguistic history suggests that a poignant moment doesn't just wash over you; it pierces your emotional defenses.

Example
The movie’s ending was so poignant that many people in the theater were crying.

May 24, 2026
sprezzatura

[sprets-uh-toor-uh]

noun
seemingly effortless stylishness

Explanation
Sprezzatura is a kind of grace where skill and style appear to come easily. But don't be fooled; looking effortlessly stylish might actually take a lot of work! The idea was popularized in Baldassare Castiglione's The Book of the Courtier, which stressed that sprezzatura is essential at a royal court. Curtsy or bow when you've mastered this word!

Example
The handsome actor had a certain sprezzatura that captivated everyone at the gala.

Where does the word mercurial derive from?

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[H1] mercurial

American

[mer-kyoor-ee-uhl]

/ mərˈkyʊər i əl /

[H2] adjective

changeable; volatile; fickle; flighty; erratic.

a mercurial nature.

Synonyms:

indecisive,

inconstant

Antonyms:

steady,

constant

animated; lively; sprightly; quick-witted.

Synonyms:

spirited

Antonyms:

phlegmatic

pertaining to, containing, or caused by the metal mercury.

(initial capital letter)

of or relating to the god Mercury.

(initial capital letter)

of or relating to the planet Mercury.

[H2] noun

Pharmacology.

a preparation of mercury used as a drug.

mercurial

British

/ mɜːˈkjʊərɪəl /

[H2] adjective

of, like, containing, or relating to mercury

volatile; lively

a mercurial temperament

(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

[H2] noun

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

[H2] Other Word Forms

mercuriality
noun

mercurially
adverb

mercurialness
noun

unmercurial
adjective

unmercurially
adverb

unmercurialness
noun

[H2] Etymology

[H3] Origin of
mercurial
First recorded in 1350–1400; Middle English, from Latin mercuriālis “of or pertaining to the god or planet Mercury”; see origin at mercury, -al 1

[H2] Explanation

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Mercurial describes someone whose mood or behavior is changeable and unpredictable, or someone who is clever, lively, and quick. With a mercurial teacher, you never know where you stand. Mercury was the ancient Roman god of commerce and messenger of the gods, and the planet Mercury was named after the Roman god. In Middle English, this adjective meant "relating to the planet or god Mercury" and derives from Latin mercuriālis, from Mercurius "Mercury." A mercurial personality has the unpredictability associated with the god Mercury or, in astrology, is supposedly influenced by the planet.
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[H2] 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.

But it will have its work cut out to placate the mercurial Republican.

From

Barron's

• Apr. 28, 2026

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Gorka can be remarkably candid and mercurial for a senior official with such a sensitive remit, according to hours of his public remarks reviewed by ProPublica.

From

Salon

• Apr. 22, 2026

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As Cassio, both Jake Roxander and Andrew Robare were notably cocky and mercurial.

From

The Wall Street Journal

• Mar. 18, 2026

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

From

Los Angeles Times

• Mar. 11, 2026

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Ac-cording to members of the extended family, his moods can be dark and mercurial, although they say his famous temper has lost much of its volatility in recent years.

From

"Into the Wild" by Jon Krakauer

[H2] Related Words

changeable

effervescent

erratic

impulsive

resilient

unpredictable

volatile

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.