The term PREFIX FOR PHYSICS OR TURF can be solved by the word ASTRO, which is a five-letter prefix. ASTRO is derived from the Greek word astron, meaning star. It is commonly used as a prefix for words related to astronomy, physics, and turf. For example, astrodynamics is the study of the motion of celestial bodies, astrobiology is the study of life in outer space, and astroturf is a type of artificial grass.