In context|physics|lang=en terms the difference between nuclide and isotope
is that
nuclide is (physics) an atomic nucleus specified by its atomic number and atomic mass while
isotope is (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).
As nouns the difference between nuclide and isotope
is that
nuclide is (physics) an atomic nucleus specified by its atomic number and atomic mass while
isotope is (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).
As a verb isotope is
(topology|transitive) to define or demonstrate an isotopy of (one map with another).