What does the term "cation" refer to?

The term "cation" refers specifically to a positively charged ion. This charge arises when an atom or molecule loses one or more electrons, resulting in an excess of protons over electrons. Since protons carry a positive charge, the overall charge of the atom becomes positive, making it a cation.

This concept is fundamental in understanding chemical bonding and reactivity, as cations play critical roles in ionic compounds and interactions in solutions. For example, in a salt like sodium chloride (NaCl), the sodium ion (Na⁺) is a cation.

The other terms represent different concepts: a negatively charged ion is called an anion, while an element with no charge refers to a neutral atom, and an ion that has lost electrons indeed describes a cation more broadly but does not define the term in terms of charge.