Chronic
Chronic refers to something that continues over an extended period of time. A chronic condition is usually long-lasting and does not easily or quickly go away.
Chronic is the opposite of acute.
References
Taber's Cyclopedic Medical Dictionary. 24th ed. Philadelphia, PA: F.A. Davis Company; 2021. www.tabers.com/tabersonline/view/Tabers-Dictionary/755133/all/chronic. Accessed December 17, 2024.