What term describes a prop or part of the set made to break upon impact?

The term that describes a prop or part of the set made to break upon impact is "Breakaway." This term is commonly used in theatre and film to refer to specially designed items that shatter or break easily for dramatic effect, such as breakaway bottles or glass panels. These props are crafted from lightweight materials or are intentionally weakened to ensure they break safely and effectively when used in performance.

This design choice enhances the realism of onstage action without posing a safety risk to actors or crew, as they generally break into safe pieces rather than sharp shards. The use of breakaway props can significantly contribute to enhancing the visual impact of a scene, allowing for dramatic moments that can engage the audience more fully.

In contrast, other terms mentioned do not refer to props designed specifically for breaking upon impact, making "Breakaway" the most accurate choice in this context.