How is a gargoyle distinct from a grotesque?

A gargoyle is specifically designed to function as a water spout, allowing rainwater to flow away from the roof of a building, thus preventing erosion of the stone walls. This functional aspect is what primarily distinguishes gargoyles from grotesques, which may take on similar forms but do not serve the practical purpose of directing water away. Although gargoyles often feature elaborate and decorative designs, their key distinguishing element is their role in architecture as functional elements, not just ornamental features. Grotesques, on the other hand, often serve no functional purpose and are typically used purely for decoration or visual storytelling in their designs. Thus, the correct identification of a gargoyle relates to its purpose as a water spout, reinforcing its practical design in addition to any aesthetic elements it may incorporate.