Toughness refers to the ability of a material or organism to withstand stress, pressure, or damage without breaking or deforming. In materials science, toughness is a critical property that indicates how well a material can absorb energy and resist fracture. It is often measured through tests that apply force until the material fails, helping engineers select appropriate materials for construction and manufacturing. In biology, toughness can describe an organism's resilience to environmental challenges, such as extreme temperatures or limited resources. For example, certain plants, like cacti, exhibit toughness by storing water and thriving in arid conditions. This adaptability allows them to survive in harsh environments where other species may not endure.