profession-n; 3 Senses

Sense Number 1: a body of specially-trained, paid workers, usually with higher education

Commentary: PROFESSION[+entity][+social][+body][+people][+worker][+specialist][+paid]
NOTE: refers to the people in the line of work

Examples:
The medical profession is divided on this issue.
It's the dental profession's largest annual meeting in North America.
Their profession has experienced significant attrition in recent years. (fewer people)

Mappings:
WordNet 3.0 Sense Numbers: 1

Sense Number 2: a specialized livelihood or occupation, usually requiring special training, higher education

Commentary: PROFESSION[+activity][+livelihood][+training][+advanced]
NOTE: refers to the activity of the work, not the people (see Sense 1)

Examples:
Mary is a lawyer by profession.
Bill switched professions mid-career.
Her chosen profession is teaching.

Mappings:
WordNet 3.0 Sense Numbers: 2

Sense Number 3: a public avowal or affirmation of something

Commentary: PROFESSION[+action][+speech_act][+avowal][+public]

Examples:
John made a profession of disbelief at the conclusions made by the study.
His artwork, especially the pietas, are a tangible profession of his Catholic faith.
Their profession of allegiance to the new government is being questioned.

Mappings:
WordNet 3.0 Sense Numbers: 3, 4