Original: In chemistry, valence, also known as valency or valence number, is a measure of the number of bonds formed by an atom of a given element. "Valence" can be defined as the number of valence bonds a given atom has formed, or can form, with one or more other atoms.
Simplified: Other meanings are at valence In Chemistry, Valence (which is sometimes called valency) is the number of chemical bonds the atoms of a certain element can form.