agate
noun
a variegated chalcedony showing curved, colored bands or other markings.
agate
American
[ag-it]
/ ˈæg ɪt /
noun
-
agates
plural
-
a variegated chalcedony showing curved, colored bands or other markings.
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a playing marble made of this substance, or of glass in imitation of it.
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Printing. a 5½-point type of a size between pearl and nonpareil.
Agate
1
British
/ ˈæɡeɪt /
noun
agate
2
British
/ ˈæɡɪt /
noun
-
an impure microcrystalline form of quartz consisting of a variegated, usually banded chalcedony, used as a gemstone and in making pestles and mortars, burnishers, and polishers. Formula: SiO 2
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a playing marble of this quartz or resembling it
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Also called: ruby. printing (formerly) a size of printer's type approximately equal to 5 1/ 2 point
agate
3
British
/ əˈɡeɪt /
adverb
agate
Scientific
/ ăg′ĭt /
Usage
What is agate? Agate is a variety of the mineral chalcedony (a type of quartz), specifically one with bands or stripes or other markings. It is often considered a gemstone. It can occur in a wide variety of colors, including white, yellow, red, and black. The key quality of agate is its banding, which is crystal that has formed in the rock. Agate is considered a semiprecious stone, which is a label assigned to some stones that have a lesser value than those considered precious. When used in jewelry, agate is often cut into a shape called a cabochon, which is polished but not cut into facets. When loose (not set in jewelry), they are often sold in the form of a geode or slab. Several forms of chalcedony are considered agates if they contain banding, including the gemstones onyx and sardonyx. Specific kinds of agate are named for their colors and patterns. For example, moss agate features a green pattern that resembles moss. Agate is one of the traditional birthstones for the months of May and June. It is associated with the zodiac sign Gemini. Example: I bought a beautiful yellow agate geode at the rock and crystal shop.
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of agate
1150–1200; Middle English ac ( c ) ate, achate, agaten (compare Dutch agaat, Old Saxon agāt, Old High German agat ), apparently < Old French agathe or Italian agata (initial stress) ≪ Medieval Latin achātēs < Greek achā́tēs
Explanation
Agate is a gemstone that's similar to quartz. Jewelry, including pins and earrings, is sometimes made from agate. Agate is mainly found in volcanic rock, and it's often distinguished by its lines or bands, a result of silicate material layering as it filled in cracks in these ancient rocks. Agate has long been used for carving ornaments and vessels, including beads, marbles, jewelry, mortars, and pestles. The name agate comes from the Greek akhates, the name of a river in Sicily where the stone was commonly found about 3,000 years ago.
Vocabulary lists containing agate
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Gold and silver inlay work and green agate stones complete the garment.
From Barron's ● Aug. 22, 2026
Joel Otterson’s intimate sculptures set moss agate in silver and brass at Ehrlich Steinberg.
From The Wall Street Journal ● Feb. 27, 2026
Adjacent to the entombed Griffin Warrior’s wrist was a carved and gold-tipped agate, almond-shaped and just 1.3 inches in length, here making its public debut outside Europe.
From Los Angeles Times ● Sep. 10, 2025
Every time TRT took the agate, she had a Bears media guide in her lap.
From Seattle Times ● Nov. 16, 2023
Her jewelry hangs there—slices of agate on long chains of raw crystal beads, collars set with moonstones, deep green bloodstones strung together, and an opal pendant, bright as fire in the sunlight.
From "The Cruel Prince" by Holly Black
In 1904, Angela Collins, the widow of one of Seattle’s most successful businessmen and former mayor, bought 45 acres at Agate Point for a weekend and summer retreat on the beach.
From Seattle Times ● Oct. 14, 2023
Latvian teenager Agate Caune used a bold strategy in heat one of the 5,000.
From Washington Times ● Aug. 23, 2023
One of the Douglas children was accused of “bringing a weapon to school for the purposes of attacking teachers,” but he had actually brought his Agate rock collection, the parents alleged.
From Los Angeles Times ● Feb. 28, 2023
Joe Agate, 27, from Chorley in Lancashire, was proudly wearing an England top around the Souk on Wednesday, but at the game he was "in disguise in The Red Wall".
From BBC ● Nov. 30, 2022
Bainbridge Island is directly across the Agate Passage.
From "I Can Make This Promise" by Christine Day
Some 75% of sales of pieces including amethyst, sea glass and agates from her business, CindyLouWho2, based in Calgary, Alberta, come from Americans.
From BBC ● Aug. 24, 2026
Each Rock Box includes a curated selection of high-quality crystals, rough rock, agates, geodes, gem collectibles and more.
From Seattle Times ● Nov. 16, 2023
Another tour de force is “Rock Shop,” which centers on a display of sliced agates and geodes in colors that verge on the artificial — each stone is a little painting edged in glitter.
From New York Times ● Sep. 16, 2021
I won more agates and marbles than anyone in school, and gradually amassed hundreds of soldiers; finally leaving them to clutter up unreachable shelves.
From The New Yorker ● Mar. 13, 2017
Cal was able to develop his marble game and set about gathering in all the chalkies and immies, glassies and agates, in the schoolyard.
From "East of Eden" by John Steinbeck
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
