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n. One of two or more atoms having the same atomic number but different mass numbers.

v. To define or demonstrate an isotopy of (one map with another).

n. Any of two or more forms of an element where the atoms have the same number of protons, but a different number of neutrons within their nuclei. As a consequence, atoms for the same isotope will have the same atomic number but a different mass number (atomic weight).

n. one of two or more atoms with the same atomic number but with different numbers of neutrons

"The U-235 isotope is the all-important factor making uranium an effective fuel for electric generating plants."

atom   

isotone    isobar   

homotope   

radioisotope    deuterium    heavy hydrogen   

isotope dilution    isotope hydrology    isotope analysis    isotope geochemistry   

tritium    isotopic    cobalt-60    iodide    deuterium    cesium    enrichment    plutonium    helium    electronegativity