hydrochloric acid

American  

noun

1. a colorless or faintly yellow, corrosive, fuming liquid, HCl, used chiefly in chemical and industrial processes.

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hydrochloric acid British  

/ ˌhaɪdrəˈklɒrɪk /

noun

1. Formerly called: muriatic acid.  the colourless or slightly yellow aqueous solution of hydrogen chloride: a strong acid used in many industrial and laboratory processes

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hydrochloric acid Scientific  

/ hī′drə-klôr′ĭk /

1. A solution of hydrogen chloride in water, forming a very strong, poisonous, corrosive acid with a sharp odor. It is used in food processing, metal cleaning, and dyeing. Small amounts of hydrochloric acid are also secreted by the stomachs of animals for digestion.

2. Also called muriatic acid

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Etymology

Origin of hydrochloric acid

First recorded in 1825–35

Compare meaning

How does hydrochloric-acid compare to similar and commonly confused words? Explore the most common comparisons:

• hydrogen chloride vs. hydrochloric acid
• muriatic acid vs. hydrochloric acid

Example Sentences

The authors of the Communications Earth and Environment paper cite, for example, research showing hydrochloric acid emitted from solid rocket launches killing fish after it leached into nearby water.

From Salon • Apr. 4, 2025

While this phenomenon has been studied in light molecules such as ammonia, oxygen, hydrochloric acid or simple carbon compounds, it has hardly been studied in molecules with heavier atoms.

From Science Daily • Dec. 2, 2024

Certain occupational exposures, such as to sulfuric or hydrochloric acid, may also put people at higher risk of enamel erosion.

From Seattle Times • Feb. 19, 2024

A break-in on June 10 at the Longmeadow, Massachusetts, city pool led to the theft of muriatic acid, a diluted form of hydrochloric acid used for cleaning.

From Washington Times • Oct. 21, 2023

Small quantities of hydrochloric acid and hydrofluoric acid are also present.

From "Cosmos" by Carl Sagan