Isotope vs. Isomer

One of two or more atoms having the same atomic number but different mass numbers.

(Chemistry) Any of two or more substances that have the same molecular formula but differ in the way their atoms are connected to each other, in the spatial orientation of their atoms, or, in the case of large molecules such as DNA, in their molecular topology.

(nuclear 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. Thus, isotopes have the same atomic number but a different mass number.

(Physics) Any of two or more nuclei with the same mass number and atomic number that have different radioactive properties and can exist in any of several energy states for a measurable period of time.

To define or demonstrate an isotopy of (one map with another).

(chemistry) Any of two or more compounds with the same molecular formula but with different structure.

One of two or more atoms with the same atomic number but with different numbers of neutrons

(physics) Any of two or more atomic nuclei with the same mass number and atomic number but with different radioactive properties. Category:en:Radioactivity

A compound which is isomeric with another body or compound; a compound having the same chemical composition as another compound; a member of an isomeric series.

A compound that exists in forms having different arrangements of atoms but the same molecular weight