Illustrated Glossary of Organic Chemistry

Diequatorial: A pair of atoms or groups that are both in an equatorial position on a cyclohexane ring.

Diequatorial conformation		Diaxial conformation

Cis-1,2-dimethylcyclohexane exists as a pair of chair conformations, which are in ring flip equilibrium. In the more stable conformation the methyl groups are diequatorial. In the less stable conformation the methyl groups are diaxial.