| isotopes | Atomic species differing in mass number but having the same atomic number. (12 Dec 1998) |
|---|---|
| oxygen isotopes | Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes. (12 Dec 1998) |
| yttrium isotopes | Stable yttrium atoms that have the same atomic number as the element yttrium, but differ in atomic weight. Y-89 is the only naturally occurring stable isotope of yttrium. (12 Dec 1998) |
| zinc isotopes | Stable zinc atoms that have the same atomic number as the element zinc, but differ in atomic weight. Zn-66-68, and 70 are stable zinc isotopes. (12 Dec 1998) |