What does covalent mean?
"Covalent" is an adjective used almost exclusively in chemistry to describe bonds in which two atoms share pairs of electrons, holding them together in a molecule. The term applies both to the bonds themselves — as in "a covalent bond" — and, more broadly, to compounds built from such bonds, as in "a covalent compound." Covalent bonding contrasts with ionic bonding, where electrons are transferred rather than shared, though many real substances show a mixture of both characters. The word derives from Latin roots meaning "together" and "having strength," reflecting how atoms combine their attractive power over electrons. It appears constantly in textbooks, research papers, and science education, from simple molecules like water and methane to vast covalent networks like diamond, whose exceptional hardness comes from an unbroken lattice of shared-electron bonds. Because it is precise and technical, "covalent" signals scientific literacy whenever it is used.
adjectiveRelating to or denoting a chemical bond in which two atoms share one or more pairs of electrons.
- (Of a chemical bond) formed by the sharing of electron pairs between atoms.
- Characterizing compounds or structures held together by such shared-electron bonds.
"In a water molecule, each hydrogen atom forms a covalent bond with the oxygen atom."
"Diamond owes its extraordinary hardness to a rigid three-dimensional network of covalent bonds."
"Unlike sodium chloride, which is ionic, methane is a covalent compound of carbon and hydrogen."
The word 'covalent' was coined by splitting 'valence' into its Latin parts — chemists literally built the term from 'co-' (together) and 'valent' (strength) to describe atoms sharing strength.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of covalent
Covalent was coined in English in the early twentieth century from the prefix "co-" (from Latin cum, "together") combined with "valent," the stem of "valence," which traces back to Latin valentia, "strength or capacity." The term was created specifically to name bonds in which atoms share electron pairs, complementing the older notion of electrovalence for ionic bonding. It shares its ultimate root with words such as "valid," "avail," and "prevail," all descending from the Latin verb valere, "to be strong."
Related word forms
How covalent is actually used
Strictly scientific register; almost never used outside chemistry and related sciences. In casual speech people usually just say 'shared electrons' rather than invoking the term directly.