mica

American

[mahy-kuh] / ˈmaɪ kə /

noun

any member of a group of minerals, hydrous silicates of aluminum with other bases, chiefly potassium, magnesium, iron, and lithium, that separate readily into thin, tough, often transparent, and usually elastic laminae; isinglass.

mica British

/ maɪˈkeɪʃəs, ˈmaɪkə /

noun

any of a group of lustrous rock-forming minerals consisting of hydrous silicates of aluminium, potassium, etc, in monoclinic crystalline form, occurring in igneous and metamorphic rock. Because of their resistance to electricity and heat they are used as dielectrics, in heating elements, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

mica Scientific

/ mī′kə /

Any of a group of hydrous aluminosilicate minerals with the general formula (K,Na,Ca)(Mg,Fe,Li,Al) _2–3 (Al,Si) ₄ O ₁₀ (OH,F) ₂ that can be split easily into thin, partly transparent sheets. Mica is common in igneous and metamorphic rocks and often occurs as flakes or sheets. It is highly resistant to heat and is used in electric fuses and other electrical equipment. Muscovite and biotite are types of mica

Other Word Forms

Derived Forms

Inflected Forms

Nouns

micas

plural

Etymology

Origin of mica

First recorded in 1700–10, mica is from the Latin word mīca crumb, morsel, grain

Vocabulary lists containing mica

Earth Science - Middle School

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Earth Science - High School

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Rocks and Minerals - Middle School and High School

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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.

California Deputy Solicitor Gen. Mica Moore urged the court to consider the danger Californians faced from unidentified, masked agents wielding military-grade weapons in the streets.

From Los Angeles Times • Apr. 22, 2026

Last year, Christie’s sold off their sister-in-law Mica Ertegun’s estate that included a $121.2 million René Magritte from 1954, “Empire of Lights.”

From The Wall Street Journal • Nov. 21, 2025

Some show off their acting chops; others, like Mica Levi and Jon Batiste, contributed indelible music to the recognized films.

From New York Times • Mar. 8, 2024

Mica Levi's music features in certain moments of the film, including its opening, with a black screen while the score takes centre stage.

From BBC • Jan. 27, 2024

I pictured folded morning papers tossed from cars, landing in driveways all over Mica.

From "Stargirl" by Jerry Spinelli

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023