profession

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An occupation or career.
• noun An occupation, such as law, medicine, or engineering, that requires considerable training and specialized study.
• noun The body of qualified persons in an occupation or field.
• noun An act or instance of professing; a declaration.
• noun An avowal of faith or belief.
• noun A faith or belief.

from The Century Dictionary.

• noun The act of professing; open declaration; public avowal or acknowledgment of one's sentiments or belief.
• noun That which is professed; a declaration; a representation or protestation; pretense; specifically, an open and formal avowal of Christian faith and purpose.
• noun The calling or occupation which one professes to understand and to follow; vocation; specifically, a vocation in which a professed knowledge of some department of science or learning is used by its practical application to affairs of others, either in advising, guiding, or teaching them, or in serving their interests or welfare in the practice of an art founded on it.
• noun The collective body of persons engaged in a calling: as, practices disgraceful to the profession; to be at the head of one's profession.
• noun The act by which a novice enters into a religious order and takes its vows. In the Roman Catholic Church he or she must be at least sixteen years of age and must have completed a year of probation.
• noun Character; nature.
• noun Synonyms Vocation, Business, etc. See occupation.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act of professing or claiming; open declaration; public avowal or acknowledgment
• noun That which one professed; a declaration; an avowal; a claim.
• noun That of which one professed knowledge; the occupation, if not mechanical, agricultural, or the like, to which one devotes one's self; the business which one professes to understand, and to follow for subsistence; calling; vocation; employment
• noun The collective body of persons engaged in a calling.
• noun (Eccl. Law.) The act of entering, or becoming a member of, a religious order.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A promise or vow made on entering a religious order.
• noun A declaration of belief, faith or of one's opinion.
• noun 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.
• noun The practitioners of such an occupation collectively.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the body of people in a learned occupation
• noun an open avowal (true or false) of some belief or opinion
• noun affirmation of acceptance of some religion or faith
• noun an occupation requiring special education (especially in the liberal arts or sciences)