multi-centre bond

https://doi.org/10.1351/goldbook.M04042
Representation of some
molecular entities
solely by localized two-electron two-centre
bonds
appears to be unsatisfactory. Instead, multi-centre bonds have to be considered in which electron pairs occupy orbitals encompassing three or more atomic centres. Examples include the three-centre bonds in diborane, the delocalized π-bonding of benzene and
bridged carbocations
.
Source:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1144 [Terms] [Paper]