a chronic or long-standing disease that is difficult to cure

a deeply ingrained habit or hobby that is difficult to break; a long-held fondness or addiction

a long-standing habit that is difficult to break or get rid of, usually referring to a bad habit

Deeply rooted malpractice or corruption that has formed over a long period and is difficult to eliminate.

(literary) an illness that is serious and has lasted a long time; a long-standing disease

(of a disease) deeply rooted and severe; critically ill

A deep-seated passion for the mountains and rivers; used to describe someone who is addicted to living in nature as a recluse or hermit.