What does bidentate mean?
Bidentate is an adjective with two related senses, both rooted in the idea of 'two teeth.' In its older, literal sense, it describes something bearing two teeth or tooth-like projections — for instance, certain insects' mandibles or plant structures described in botanical and zoological texts. Its dominant modern usage, however, lies in chemistry, where it characterizes a ligand capable of attaching to a central metal atom through two separate donor atoms simultaneously. Familiar examples include ethylenediamine and oxalate, which 'bite' onto metals with two points at once; such chelating behavior gives rise to stable ring-shaped complexes. The word appears almost exclusively in formal, scientific writing and pairs naturally with terms like ligand and coordination. Understanding bidentate offers a window into how chemists picture molecules as creatures that grip — quite literally with two teeth — the metal centers they bind.
Having two teeth or tooth-like projections.
"The fossil fish was identified by its bidentate jaw spines."
Most often encountered in technical biological description.
(Of a ligand in coordination chemistry) Binding to a central metal atom through two donor atoms.
"Bipyridine is a widely used bidentate ligand in organometallic catalysis."
Contrasts with monodentate and tridentate; part of the series mono-/bi-/tri-/tetradentate.
In chemistry, a bidentate ligand doesn't just bond to a metal — it grabs it with two hands, like a tiny molecular claw.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of bidentate
Bidentate derives from Latin bi-, meaning 'two,' combined with dens (stem dent-), meaning 'tooth,' plus the adjectival suffix -ate. It entered English in the mid-nineteenth century, first in descriptive biology before being adopted by chemists as coordination theory developed. It shares its Latin root dens with words such as dental, dentist, and trident.
How bidentate is actually used
Predominantly technical vocabulary, found mainly in zoology, botany, and especially coordination chemistry. In chemistry contexts it contrasts with monodentate, tridentate, etc., describing how many donor atoms a ligand uses.
Easily confused with bidentate
Edentate means lacking teeth (as in the order including anteaters), while bidentate means having two tooth-like projections.