regeneration

(countable, uncountable) Rebuilding or restructuring; large scale repair or renewal; revitalisation.
(countable, uncountable) Spiritual rebirth; the change from a carnal or material life to a pious one
(countable, uncountable) The renewal of the world at the second coming of Christ.
(countable, uncountable) The process by which a water softener flushes out minerals extracted from the water supply.
(countable, uncountable) The ability to rapidly heal substantial physical damage to one's body, or to spontaneously restore hit points.
(countable, uncountable) The property of a kind of circuit, much used in radio receivers, that allows an electronic signal to be amplified many times through a feedback loop.