What do you call a person who works solely with one company for a fixed salary?

The term for a person who works solely with one company for a fixed salary is "contracted employee." This type of employment indicates a stable relationship between the individual and the company, where the employee is typically on the payroll and receives a regular salary, along with potential benefits. Contracted employees are bound by the terms of their contract, which generally outlines their responsibilities, working hours, and compensation.

In contrast, freelancers tend to work for multiple clients and often on a project basis, rather than being tied to a single employer. Independent contractors have a similar nature to freelancers but may operate under specific contracts for services without the benefits and obligations typically associated with employment. Casual workers usually have a flexible work arrangement and may not have guaranteed hours or salary, making this term unsuitable for someone who works for one company with a fixed salary. Thus, the definition of a contracted employee aligns perfectly with a person engaged in long-term employment with a single entity.