limestone

American  

[lahym-stohn] / ˈlaɪmˌstoʊn /

noun

1. a sedimentary rock consisting predominantly of calcium carbonate, varieties of which are formed from the skeletons of marine microorganisms and coral: used as a building stone and in the manufacture of lime.

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limestone British  

/ ˈlaɪmˌstəʊn /

noun

1. a sedimentary rock consisting mainly of calcium carbonate, deposited as the calcareous remains of marine animals or chemically precipitated from the sea: used as a building stone and in the manufacture of cement, lime, etc

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limestone Scientific  

/ līm′stōn′ /

1. A sedimentary rock consisting primarily of calcium carbonate, often in the form of the minerals calcite or aragonite, and sometimes with magnesium carbonate in the form of dolomite. Minor amounts of silica, feldspar, pyrite, and clay may also be present. Limestone can occur in many colors but is usually white, gray, or black. It forms either through the accumulation and compaction of fossil shells or other calcium-carbonate based marine organisms, such as coral, or through the chemical precipitation of calcium carbonate out of sea water.

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limestone Cultural  

1. Sedimentary rock formed primarily of calcium carbonate, often the skeletons of small marine organisms.

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Etymology

Origin of limestone

First recorded in 1515–25; lime ² + stone

Compare meaning

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

• limestone vs. travertine

Example Sentences

He noted that one Limestone unit produced about 58% more electricity last year from a year earlier, while a second unit produced 25% more, according to the EPA data.

From The Wall Street Journal • Feb. 26, 2026

Limestone and chalk are formed from the deposit and compression of micro-organisms found in shallow warm seas.

From BBC • Feb. 19, 2025

In January, Uno, a female mountain lion often seen patrolling the mountains in Orange County, was killed after being struck by a vehicle on a road near the Limestone Canyon Nature Preserve.

From Los Angeles Times • Jun. 15, 2024

In no time, the Limestone University track standout was putting her speed and agility to use for the national team, where she scored four TDs in the gold-medal game versus Mexico last summer.

From Seattle Times • Dec. 28, 2023

One day in June a letter came from a tennis coach from a college named Limestone in Gaffney, South Carolina.

From "Kaffir Boy: An Autobiography" by Mark Mathabane