Physicist (noun)

1. A person who specializes in the study of physics, the branch of science concerned with the nature and properties of matter and energy.
2. A person who is an expert in the field of physics and its applications.

Origin:

From the latin word physica ("natural philosophy") + -ist. the word was first used in the late 19th century.

Examples:

1. He is a physicist and works in the field of quantum mechanics.
2. The physicist developed a new theory of the universe.
3. She is a physicist and teaches at the university.
4. The physicist's research led to the discovery of new particles.
5. The physicist's work has contributed to the advancement of technology.