Ekacitta

ekacitta, a mind with singular focus (but literally meaning ‘one mind’) becomes the metaphysical one mind of the Awakening of Faith in Mahāyāna.

The ‘one thought-moment’ out of time, in which the Zen monk experiences Non-duality, that state before the One became the Many, before thought was born. Cp. Ichinen, Kenshō, Satori.