In the Buddhist suttas samadhi is defined as mental one-pointedness. This definition is followed through rigorously in the Abhidhamma. The Abhidhamma treats one-pointedness as a distinct mental factor present in every state of consciousness, exercising the function of unifying the mind on its object. This unifying factor is topic-neutral and can be present in any state of consciousness.
In expositions on the practice of meditation, however, samadhi is limited to one-pointedness of mind. Thus Buddhaghosa defines samadhi as “the centering of consciousness and consciousness concomitants evenly and rightly on a single object … the state in virtue of which consciousness and its concomitants remain evenly and rightly on a single object, undistracted and unscattered” (Vism.84-85; PP.85).
The analog in Patanjali’s yoga system is Dhāraṇā, defined as “collection or concentration of the mind (joined with the retention of breath)” or “the act of holding, bearing, wearing, supporting, maintaining, retaining, keeping back (in remembrance), a good memory.” (The term is related to the verbal root dhri to hold, carry, maintain, resolve.)
In the state of Dhāraṇā, the mind thinks about one object only and avoids all other thoughts. Awareness of the object can be interrupted and still qualify as Dhāraṇā.
Dhāraṇā is the initial step of the three-step process of deep concentrative meditation where an object is held in the mind without wavering of consciousness:
- Dhāraṇā—The object of meditation, the meditator, and the act of meditation itself remain separate. The meditator is self-conscious of meditating, of the act and effort, and of the object.
- Dhyāna—In the subsequent stage of Dhyāna, consciousness of the act of meditation disappears, and only the consciousness of awareness and its object exist.
- Samādhi—Finally, in the stage of Samādhi, the ego-mind also dissolves, and the meditator becomes one with the object.