From Ancient Greek ἴσος (ísos, “equal; same”) and τόπος (tópos, “place”), because the different isotopes of a chemical element always occupy the same position in the periodic table of elements. The term was coined in 1909 by Scottish doctor Margaret Todd and first used publicly on February 27, 1913 by English chemist Frederick Soddy.
isotope (plural isotopes)
- (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).
Possible back-formation from isotopy.
isotope m, f (plural isotopes)
- isotopic (relating to isotopes)
isotope m (plural isotopes)
- “isotope” in le Trésor de la langue française informatisé (The Digitized Treasury of the French Language).
- inflected form of