What is the meaning of Regeneration?

Rebuilding or restructuring; large scale repair or renewal; revitalisation.

Spiritual rebirth; the change from a carnal or material life to a pious one

The renewal of the world at the second coming of Christ.

The process by which a water softener flushes out minerals extracted from the water supply.

The ability to rapidly heal substantial physical damage to one's body, or to spontaneously restore hit points.

Source: wiktionary.org