mercury
noun
mer·cu·ry
ˈmər-kyə-rē 
-k(ə-)rē
plural mercuries
1
a
Mercury
: a Roman god of commerce, eloquence, travel, cunning, and theft who serves as messenger to the other gods compare hermes
b
often Mercury archaic
: a bearer of messages or news or a conductor of travelers
2
[Middle English mercurie, from Medieval Latin mercurius, from Latin, the god]
a
: a silver-white poisonous heavy metallic element that is liquid at ordinary temperatures and is used especially in batteries, in dental amalgam, and in scientific instruments
called also quicksilver
see Chemical Elements Table
b
: the column of mercury in a thermometer or barometer
3
Mercury
: the planet nearest the sun see Planets Table
Examples of mercury in a Sentence
In the summer, the mercury can reach over 100 degrees Fahrenheit.
Recent Examples on the Web
Scorching temperatures in the 90s have gripped the city for the past several days, with the mercury hitting 100 degrees in Central Park on Thursday afternoon.
—
Julian Roberts-Grmela,
New York Daily News,
4 July 2026
Research indicates that certain protein powders contain concerning levels of harmful metals, including cadmium, mercury, and lead.
—
Anna Giorgi,
Verywell Health,
3 July 2026
The highest official temperature reading for Chicago was a day later, on July 24, 1934, when the mercury hit 105 at the University of Chicago — the city's official temperature recording site before O'Hare International Airport.
—
Adam Harrington,
CBS News,
1 July 2026
Mercury stations retrograde in Cancer in your 11th House of Friends and Community, bringing old invitations, group-chat confusion, or unclear expectations back into focus.
—
Tarot.com,
Sun Sentinel,
29 June 2026
See All Example Sentences for mercury
Examples are automatically compiled from online sources to
show current usage.
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Julian Roberts-Grmela,
New York Daily News,
4 July 2026
Research indicates that certain protein powders contain concerning levels of harmful metals, including cadmium, mercury, and lead.
—
Anna Giorgi,
Verywell Health,
3 July 2026
The highest official temperature reading for Chicago was a day later, on July 24, 1934, when the mercury hit 105 at the University of Chicago — the city's official temperature recording site before O'Hare International Airport.
—
Adam Harrington,
CBS News,
1 July 2026
Mercury stations retrograde in Cancer in your 11th House of Friends and Community, bringing old invitations, group-chat confusion, or unclear expectations back into focus.
—
Tarot.com,
Sun Sentinel,
29 June 2026
See All Example Sentences for mercury
Cite this Entry
“Mercury.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mercury. Accessed 5 Jul. 2026.
Copy CitationKids Definition
mercury
noun
mer·cu·ry
ˈmər-kyə-rē
-k(ə-)rē
Medical Definition
mercury
noun
mer·cu·ry
ˈmər-kyə-rē, -k(ə-)rē
plural mercuries
1
: a heavy silver-white poisonous metallic element that is liquid at ordinary temperatures and used especially in scientific instruments
—symbol Hg
called also quicksilver
see Chemical Elements Table2
: a pharmaceutical preparation containing mercury or a compound of it
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