ordination
This term carries a heavy weight of solemnity and spiritual transformation. It is not merely a graduation or a promotion, but a ritualistic transition that changes a person's status within a religious hierarchy, often implying a divine calling rather than a personal career choice. In a broader, non-religious sense, it can describe the formal appointment of someone to a high office, though this usage is rare and highly formal. It evokes an image of ceremony, tradition, and the acceptance of a lifelong burden of service to a community.
Countable when referring to the specific ceremony itself (the ordination took place on Sunday). Uncountable when referring to the general state or process of being ordained (ordination requires years of study).