Maturation

The process of bringing, or of coming, to maturity; hence, specifically, the process of suppurating perfectly; the formation of pus or matter.

(medicine) the formation of morbific matter in an abscess or a vesicle and the discharge of pus

(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; "he proposed an indicator of osseous development in children"