The best replacement for isotopes is ions.

The best alternatives to isotopes are rated as following:
★★★★★  ions
★★★★  radioisotopes
★★★  isomers
★★  different elements
★★  allotropes
★  isobars
  elements
  nuclides
  non radioactive isotopes
  isotopes
  stable isotopes
  atomic number

Your alternative for isotopes is not listed? Suggest!
Speaking about isotopes, one probably shouldn't forget about amu.

Other search terms related to isotopes and their ratings are:
★★★★★ amu
★★★ atomic masses
★★ elements
★★ atoms
You have in mind a companion for isotopes and it is not yet here? Propose!



Google Trends

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isotopes
ions
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