What is the difference between a: butler, house manager, majordomo, estate manager & chief of staff

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There are a lot of job titals in the family office and private staffing. Rachel Stallard and I examine some of the different titals,

House manager - Overseeing the smooth running of the house and ensuring good general upkeep and maintenance of the property and land. Also, the House Manager may supervise other household staff. ... However, smaller households may combine Butler and House Manager, or Housekeeper, and House Manager into one role

A majordomo is a person who speaks, makes arrangements or takes charge for another. Typically, this is the highest (major) person of a household (domūs or domicile) staff, a head servant who acts on behalf of the owner of a large or significant residence.

A butler is a person who works in a house serving and is a domestic worker in a large household. In great houses, the household is sometimes divided into departments with the butler in charge of the dining room, wine cellar, and pantry.

The chief of staff role is defined by its ability to provide strategic counsel to key leaders within organizations. While the day-to-day responsibilities vary dramatically across industries and companies, the position is an increasingly critical component in supporting a successful leadership team.