Prana has been defined as life force energy.  Some alternative terms from other belief systems may be chi, or qi.  It is the energy that flows through our being.  As one works with their chakra energy systems the ability to sense the prana flowing through becomes more profound.

Feeling the force (prana) flow can be a form of meditation.

All definitions here are based on my understanding, learning and reading of Kundalini and other Yoga related texts, classes and websites.

I invite the Kundalini Yoga experts in the community to ellaborate on what I have presented here, and thus further the learning experience for visitors.