What term refers to an establishment providing services in one or more fields of practice?

The term that best describes an establishment providing services in one or more fields of practice is "facility." A facility typically refers to a specific location or establishment where services, such as healthcare, education, or recreational activities, are offered. This term encompasses a variety of contexts, indicating that it is not just a single service but can include multiple areas of expertise and operations under one roof.

In contrast, "agency" generally implies a business entity that facilitates services but does not necessarily provide multiple service fields directly. "License" refers to a legal authorization to practice a profession or conduct a certain activity but does not describe an establishment itself. "Freelance" indicates a work style where individuals provide services independently rather than through a formalized establishment, which does not align with the concept of an establishment providing diverse services.