A transverse intersection of two manifolds is defined as clean when the tangent spaces at the intersection point span the tangent space of the larger manifold. Clean intersections imply that the intersection itself is an embedded manifold. However, the converse does not hold true, as a clean intersection does not guarantee that the original manifolds are transverse. The discussion references the implicit function theorem as a key component in proving the forward statement. For further clarification, the link provided and Guillemin and Pollack's text are suggested resources.