Expertise/ˌekspɜːrˈtiːz/ Definition 1 of 1Pro Tip 1/3Specialized Knowledge Expertise implies deep understanding in a specific field, often acquired over time. His expertise in ancient languages is unparalleled. Pro Tip 2/3Not Beginner's Level Expertise is more than basic knowledge; it suggests a high-level, expert status. She offers expertise in environmental law. Pro Tip 3/3Professional Context Use 'expertise' in professional or academic contexts where credibility matters. He contributed his technical expertise to the project.