What is an individual who provides professional advice or services for a fee, typically not as an employee, called?

The term that best fits the description of an individual who provides professional advice or services for a fee, typically not as an employee, is "consultant." A consultant usually has specialized knowledge or skills in a certain area and offers their expertise to organizations or individuals seeking guidance in that field. This role is usually defined by a formal agreement or contract outlining the scope of the work, the fees, and the duration of the engagement.

While an advisor may also provide professional guidance, this term often implies a more ongoing relationship, possibly involving a more permanent or embedded role within an organization.

A contractor typically refers to someone who undertakes projects or job tasks based on a specific agreement or for a fixed period, generally with a focus on delivering specific outputs rather than ongoing advisory services.

A freelancer, on the other hand, encompasses a broader category of workers who take on various project-based tasks across diverse fields, often without long-term commitments to any single client. While freelancers may provide consultation services, the term "consultant" is more specific to those offering expert advice as a primary part of their work.

This makes "consultant" the most accurate term for the role described.