mercury

noun

mer·​cu·​ry ˈmər-kyə-rē 

-k(ə-)rē

plural mercuries

1

a

capitalized : a Roman god of commerce, eloquence, travel, cunning, and theft who serves as messenger to the other gods compare hermes

b

often capitalized 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

also : temperature

the mercury rose above 70 degrees

3

capitalized : 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

Excessive consumption can lead to mercury poisoning, which may cause severe or even life-threatening health complications. —George Monastiriakos, Newsweek, 31 Dec. 2024

And groups like the Environmental Integrity Project and the Sierra Club have denounced it as a leading polluter of mercury among Texas power plants and expressed concern that two coal ash ponds are causing chemicals to seep into groundwater in the area. —Juan Salinas Ii, Austin American-Statesman, 27 Dec. 2024

The analysis detected elements such as nickel, copper, zinc, tin, mercury, gold, lead and a big surprise: tungsten, which hadn’t even been described at the time. —Cnn, The Mercury News, 25 Dec. 2024

Making small swaps like using a deep burgundy ribbon instead of a bright red one on wreaths or adding black ornaments to a collection of mercury glass baubles is a simple (but impactful) way to put a moody spin on you Christmas decorating this season. —Maria Sabella, Better Homes & Gardens, 16 Dec. 2024

Word History

Etymology

Latin Mercurius, Roman god and the planet

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing mercury

• bichloride of mercury
• mercury chloride
• mercury-vapor lamp

Kids Definition

mercury

noun

mer·​cu·​ry ˈmər-kyə-rē 

-k(ə-)rē

1

a

: a heavy silver-white poisonous metallic element that is liquid at ordinary temperatures

called also quicksilver

see element

b

: the column of mercury in a formerly common type of thermometer or barometer

2

capitalized : the planet nearest the sun see planet

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 Table

2

: a pharmaceutical preparation containing mercury or a compound of it