On Perfect Absorption - Samadhi

Samadhi is the eighth limb of Patanjali's astanga yoga.

In book three of Patanjali's yoga sutras he says:

Y.S. III.3 tadeva arthamatranirbhasam svarupasunyam iva samadhih
As translated by B.K.S. Iyengar in Light on the Yoga Sutras of Pantanjali:

When the object of meditation engulfs the meditator, appearing as the subject, self-awareness is lost.  This is samadhi.

For the many of us who have not experienced samadhi this is a challenging concept to understand. 
Mr. Iyengar helps to explain saying that,

"When the attentive flow of consciousness merges with the object of meditation, the consciousness of the meditator, the subject, appears to be dissolved in the object.  This union of subject and object becomes samadhi."

He further states that,

"Uninterrupted flow of attention dissolves the split between the object seen and the seer who sees it.  Consciousness appears to have ceased, and to have reached a state of silence.  It is devoid of "I", and merges into the core of the being in a profound state of serenity.  In samadhi, awareness of place vanishes and one ceases to experience space and time."

Samadhi defined means, perfect absorption, intent attention, union, bringing into harmony or spiritual absorption.
I wish you well on your journey.

Namaste.
Pamela Nelson
http://www.plnyoga.vpweb.com/