periodic table

American  

[peer-ee-od-ik, peer-] / ˈpɪər iˈɒd ɪk, ˌpɪər- /

noun

Chemistry.

1. a table illustrating the periodic system, in which the chemical elements, formerly arranged in the order of their atomic weights and now according to their atomic numbers, are shown in related groups.

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periodic table British  

/ ˌpɪərɪˈɒdɪk /

noun

1. a table of the elements, arranged in order of increasing atomic number, based on the periodic law. Elements having similar chemical properties and electronic structures appear in vertical columns (groups)

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Periodic Table Scientific  

1. A table in which the chemical elements are arranged in order of increasing atomic number. Elements with similar properties are arranged in the same column (called a group), and elements with the same number of electron shells are arranged in the same row (called a period).

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Etymology

Origin of periodic table

First recorded in 1890–95

Example Sentences

Every character has an adorable quirk or two, or at minimum owns a dorky T-shirt with a periodic table joke or a cartoon cat.

From Los Angeles Times • Mar. 18, 2026

These include scandium, yttrium and the lanthanides, which account for 15 chemical elements in the periodic table.

From MarketWatch • Oct. 28, 2025

One of the most critical rare earths is dysprosium, atomic number 66 on the periodic table.

From The Wall Street Journal • Oct. 11, 2025

The phrase "rare earths" - referring to 17 elements on the periodic table which are lightweight, super strong and resistant to heat, making them useful in small electric motors - is something of a misnomer.

From BBC • Aug. 12, 2025

“Hey, yo, Mr. Knatvold, what’s the periodic table of kryptonite?”

From "Everything Sad Is Untrue" by Daniel Nayeri