Legal Definition of Durable: Able to remain in existence for a long period of time regardless of the existence of obstacles, impediments or other adverse conditions. A power of attorney is said to be durable if it remains in effect even after the principal becomes incapacitated or incompetent | Learn the legal definition of durable and how it affects powers of attorney. Discover why having a durable power of attorney is crucial for business owners, ensuring continuity even in challenging circumstances