[ˈʌɪsətəʊp], (Noun)

Definitions:
- each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element
(e.g: some elements have only one stable isotope)


Phrases:

Origin:
1913: coined by F. Soddy, from iso- ‘equal’ + Greek topos ‘place’ (because the isotopes occupy the same place in the periodic table of elements)