Concentration partaking of penetration (Buddhism)

In this state there is accessibility to perception and attention which is accompanied by dispassion and directed towards fading away.

According to Hinayana Buddhism, concentration is considered as of one kind (monad), of two kinds (dyads), of three kinds (triads), of four kinds (tetrads) or of five kinds (pentad). In the fourth tetrad, where concentration is associated with different conditions of wisdom or understanding, this is the fourth concentration.