bailiwick

noun

1. The district within which a bailie or bailiff has jurisdiction.

   “The Bailiwick of Jersey.”

2. (broadly)A person's concern or sphere of operations, their area of skill or authority.

   “I established the fairly well-understood pattern that affairs of state were not in my bailiwick.”

   “Jack is full of these insights, thoughtful turns of phrase from a character whose perpetual struggle between wastrel and righteous is all too familiar a bailiwick for the universal insecurities of the human condition.”

   “This “feminist chortling” (as she calls it) about the disgraced royal is right in the bailiwick of the writer who virtually invented the term mansplaining.”