Dhāraṇā is the sixth stage, step or limb of eight elucidated by Patanjali’s Ashtanga Yoga or Raja Yoga: “holding”, “holding steady”, “concentration” or “single focus”. Dhāraṇā is the initial step of deep concentrative meditation, where the object being focused upon is held in the mind without consciousness wavering from it; the object of meditation, the meditator, and the act of meditation itself remain separate.

The meditator or the meditator’s meta-awareness is conscious of meditating (that is, is conscious of the act of meditation) on an object, and of his or her own self, which is concentrating on the object. In the subsequent stage of Dhāraṇā, as the meditator becomes more advanced, consciousness of the act of meditation disappears, and only the consciousness of being/existing and the object of concentration exist (in the mind).

Bhagavad Gita, ~Ch. 6, V34:

The mind is restless, turbulent and strong, as difficult to curb as the wind.