Definition of crown

1. A molecular entity comprising a monocyclic ligand assembly that contains three or more binding sites held together by covalent bonds and capable of binding a guest in a central (or nearly central) position. The adducts formed are sometimes known as "coronates". The best known members of this group are macrocyclic polyethers, such as "18-crown-6", containing several repeating units -CR2-CR2O- (where R is most commonly H), and known as crown ethers. PEDERSEN (1967); CRAM et al. (1986).

   See also host.