WordNet sense 1 ((biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level):

development, growth, maturation, ontogeny, ontogenesis

WordNet sense 2 (having or showing vigorous vegetal or animal life):

thriving, flourishing

WordNet sense 3 (having or indicating good health in body or mind; free from infirmity or disease):

healthy