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

The effects of mercury exposure can be severe, subtle or non-existent depending on factors such as the form of mercury, the amount of mercury in the exposure, the age of the person exposed and how long the exposure lasts, according to the EPA's website. —Bebe Hodges, The Enquirer, 28 Nov. 2024

Weldon was one of the sponsors of a bill that would have banned mercury from vaccines. —Sareen Habeshian, Axios, 22 Nov. 2024

Light Faux Mercury-Style Pumpkins: $32.99 For a bit of seasonal ambiance, this 3-piece light-up mercury glass pumpkin centerpiece from Wayfair is perfect for setting a warm, cozy tone in your kitchen. —Jené Luciani Sena, Fox News, 6 Nov. 2024

The high temperatures will also push mercury levels into the 80s across the entire Southeast, from Texas to Florida and up through the Carolinas. —Christopher Cann, USA TODAY, 31 Oct. 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