What is the term for the body's natural ability to heal itself?

The term that best describes the body's natural ability to heal itself is homeostasis. Homeostasis refers to the processes that maintain equilibrium or balance within the body's internal environment, despite external changes. This concept encompasses various physiological systems working together to regulate factors such as temperature, pH levels, and other vital conditions necessary for health and survival.

Homeostasis not only involves maintenance of stability but also incorporates the body's capacity to respond to injury and illness. When the body experiences a disruption, mechanisms are activated to restore balance. For example, in the case of an injury, systems initiate inflammation, tissue repair, and other healing responses, which are all part of the homeostatic process.

Regeneration, while related to the healing process, specifically refers to the growth of new tissue to replace lost or damaged tissue, which is a narrower aspect of the broader concept of homeostasis. Adaptation involves adjustments in response to changing circumstances (like stress or acclimatization), and metabolism refers to the biochemical processes that occur within living organisms to maintain life, including the conversion of food into energy but does not directly denote the body's healing processes.