The union of two separate, normally distinct tooth germs during development, resulting in one fewer tooth than the expected count in the arch, describes which anomaly?

Fusion is the union of two separate tooth germs during development, typically resulting in a single, larger tooth structure and one fewer tooth than the normal expected count — distinguishing it from gemination, which originates from a single bud attempting to divide (preserving normal tooth count) and from concrescence, which involves union of two fully-formed roots via cementum only, after development is complete.