isotope

  1. Noun.  (physics) 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).
  2. Verb.  (topology, transitive) To define or demonstrate an isotopy of (one map with another).

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This entry was last updated on RefTopia from its source on 3/20/2012.