What is "heptalene"

n. (context organic compound English) A bicyclic hydrocarbon consisting of two fused cycloheptatriene rings

Heptalene is a polycyclic hydrocarbon with chemical formula CH, composed of two fused cycloheptatriene rings. It is an unstable, non-planar compound which is non-aromatic. The dianion, however, satisfies Hückel's rule, is thermally stable, and is planar.