Functionalist (noun)

1. An advocate or supporter of functionalism, a theory or approach that emphasizes the practical uses and purposes of something, especially in architecture, design, and social theory.
2. A person who believes that the function or purpose of something is more important than its form or appearance.

Origin:

Early 20th century: from functional + -ist.

Examples:

1. He was a functionalist architect, designing buildings that were functional and efficient.
2. The functionalist approach emphasized the practical uses of the building.
3. The functionalist believed that the function of the building was more important than its appearance.
4. He was a functionalist in his approach to design.
5. The functionalist believed that the function of the society was more important than its appearance.