An occupation, trade, craft, or activity in which one has a professed expertise in a particular area; a job, especially one requiring a high level of skill or training.
The practitioners of such an occupation collectively.
The declaration of belief in the principles of a religion; hence, one's faith or religion.
A promise or vow made on entering a religious order.
Any declaration of belief, faith or one's opinion, whether genuine or (as now often implied) pretended.
Someone who is up-and-coming, who has begun to be successful in some field and is likely to be even more successful in the future.