Isotope

An atom of an element with a particular number of neutrons. Isotopes of the same element have the same number of protons but different numbers of neutrons.

An atom of an element with the same number of protons but a different number of neutrons compared with another atom of that element.

An atom of an element with the same number of protons but a different number of neutrons from another atom of that element.

One of two or more forms of an element whose atoms have the same number of protons but different numbers of neutrons.