What term describes teachers' knowledge about the subject matter to be learned or taught?

The correct term to describe teachers' knowledge about the subject matter to be learned or taught is indeed "Content Knowledge." This refers specifically to the understanding and mastery that educators have of the subjects they are responsible for teaching. Teachers with strong content knowledge possess a deep grasp of the concepts, facts, theories, and principles of their subject area, enabling them to effectively convey this information to their students and respond to questions or misconceptions that may arise.

While pedagogy refers to the methods and practices of teaching, it does not specifically denote the subject matter knowledge itself. Curriculum defines the structured content and academic standards that guide what is to be taught but does not encompass the teachers' personal knowledge of that content. Teaching strategies refer to the specific techniques and approaches that educators use in the classroom to facilitate learning, but again, these strategies are distinct from the underlying knowledge of the content itself.