https://doi.org/10.1351/goldbook.AT06984
The manner of interaction (termed according to the Greek 'to hold or clasp to oneself as a shield') of a coordinatively unsaturated metal atom with a ligand, when the metal atom draws the ligand towards itself. An important type of @[email protected] interaction is the C–H–Metal @[email protected] providing for the @[email protected] of the C–H bond in transition metal complexes.