Astrophysics (noun)

1. A branch of astronomy that deals with the physical properties and behavior of celestial objects and phenomena.
2. The study of the properties and behavior of celestial objects and the physical processes that govern them.

Origin:

Late 19th century: from astro- + physics.

Examples:

1. He studied astrophysics to understand how stars form.
2. The astrophysics department at the university is renowned for its research on black holes.
3. Astrophysics is the study of the physical and chemical properties of celestial objects and their behavior.
4. The telescope was used to study the astrophysics of the galaxy.
5. The astrophysics of the universe is a complex and ever-changing field of study.