1. a scientist who studies rocks, their composition, structure, and formation
Usage: geology

Examples

• The petrologist examined the volcanic rock samples under a microscope.
• She became a petrologist after studying geology in college.
• The petrologist identified the mineral composition of the ancient granite.
• Our team includes a petrologist who specializes in sedimentary rocks.
• The petrologist’s research focused on how metamorphic rocks form under pressure.
• A skilled petrologist can determine a rock’s age and origin.