isotope

1 of 2

noun

iso·tope ˈī-sə-ˌtōp

: any of two or more species of atoms of a chemical element with the same atomic number and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties

: nuclide

isotopic

ˌī-sə-ˈtä-pik -ˈtō-

adjective

isotopically

ˌī-sə-ˈtä-pi-k(ə-)lē -ˈtō-

adverb

isotopic

2 of 2

adjective

iso·topic

-¦tōp-

: of, relating to, or having the relationship of an isotope

isotopically

-pə̇k(ə)lē

adverb

Examples of isotope in a Sentence

Recent Examples on the Web

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Noun

To get a better understanding of who this individual was, researchers have spent the past few years conducting a detailed analysis of the remains’ DNA and isotopes, and the chemical properties of the metallic artefacts and the decorative band. — Mike McRae 25, New Atlas, 26 Aug. 2026 The latter is a rare isotope embedded in lunar soil that could become a major fuel source and has a use for cooling quantum computing systems. — Amanda Gerut, Fortune, 26 Aug. 2026 As part of its nuclear fusion processes, the Sun produces a particularly interesting isotope of helium, known as helium-3. — Eric Berger, ArsTechnica, 26 Aug. 2026 Also, its strontium (Sr) and lead (Pb) isotope signatures are virtually identical to those of the underlying carbonatite rock. — Mrigakshi Dixit, Interesting Engineering, 24 Aug. 2026 See All Example Sentences for isotope

Word History

Etymology

Noun

is- + Greek topos place

Adjective

International Scientific Vocabulary isotope + -ic

First Known Use

Noun

1913, in the meaning defined at sense 1

Time Traveler

The first known use of isotope was in 1913

See more words from the same year

Cite this Entry

Style

“Isotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isotope. Accessed 1 Sep. 2026.

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Kids Definition

isotope

noun

iso·tope ˈī-sə-ˌtōp

: any of the forms of an element that differ in the number of neutrons in an atom

isotopic

ˌī-sə-ˈtäp-ik

-ˈtō-pik

adjective

isotopically

-ˈtäp-i-k(ə-)lē

-ˈtō-pi-

adverb

Medical Definition

isotope

noun

iso·tope ˈī-sə-ˌtōp

: any of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties

: nuclide

isotopic

ˌī-sə-ˈtäp-ik -ˈtō-pik

adjective

isotopically

-ˈtäp-i-k(ə-)lē -ˈtō-pi-

adverb

isotopy

ˈī-sə-ˌtō-pē ī-ˈsät-ə-pē

noun

plural isotopies

isotope

noun

adjective

Examples of isotope in a Sentence

Word History

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isotope

noun

adjective

Examples of isotope in a Sentence

Word History

Rhymes for isotope

Browse Nearby Words

Cite this Entry

Kids Definition

Medical Definition

More from Merriam-Webster on isotope

More from Merriam-Webster

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conscientious

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