The term "nucleon number" refers to the total number of nucleons, which include the number of protons and neutrons, in the nucleus of an atom. Some synonyms for nucleon number include atomic mass number, mass number, and simply nucleon count. Atomic mass number indicates the number of nucleons in the nucleus of one atom of an element, while mass number represents the sum of the number of protons and the number of neutrons in an atom. Nucleon count is a more general term used to describe any count of protons and neutrons, but it is often used interchangeably with mass number in scientific contexts.