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isotope - definition and synonyms


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noun [countable] chemistry isotope pronunciation in American English /ˈaɪsəˌtoʊp/
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  1. one of the forms of a chemical element that have the same atomic number because they have the same number of protons, but have a different number of neutrons, and therefore have a different mass


used to describe something which is done more carefully and over a longer period of time …

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the practice of giving birth in the presence of several friends and relatives

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