What is the term for the ability of a substance to be stretched or deformed without breaking?

The term that describes the ability of a substance to be stretched or deformed without breaking is ductility. Ductility specifically refers to a material's capacity to be drawn into a wire or to undergo significant deformation before fracture, demonstrating its plastic behavior under tensile stress. This property is especially significant in metals, such as copper and aluminum, which can be easily molded or drawn into thin wires without losing their structural integrity.

Other terms provided in the options have distinct meanings. Elasticity refers to a material's ability to return to its original shape after being stretched or deformed. Malleability denotes the ability of a material to be hammered or rolled into thin sheets, focusing more on compressive deformation than tensile. Strength relates to a material's ability to withstand an applied force without failure but does not necessarily imply the ability to undergo significant deformation. Thus, ductility is the precise term that aligns with the ability to stretch and deform without breaking.