Simple Definition of isotope

from our Learner's Dictionary

isotope

noun

ˈaɪsəˌtoʊp

plural isotopes

chemistry : any one of various forms in which the atoms of a chemical element can occur

carbon isotopes

radioactive isotopes

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“Isotope.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/isotope. Accessed 19 Jun. 2026.

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