electrovalent bond (ionic bond) A type of chemical bond formed by the transfer of one or more electrons from one atom to another, so that oppositely charged ions are produced. For example, the bond between the sodium and chlorine atoms in sodium chloride (NaCl) is formed by the transfer of an electron from sodium to chlorine, creating Na⁺ and Cl^– ions. The electrostatic attraction between these ions provides the bonding in NaCl.

electrovalent bond See ionic bond.