Dictionary.net

having a habit of long standing; "a chronic smoker"

being long-lasting and recurrent or characterized by long suffering; "chronic indigestion"; "a chronic shortage of funds"; "a chronic invalid"

having a habit of long standing; "a chronic smoker"

Continuing for a long time; returning again and again; said of a disease.

Of long duration, noting a disease of slow progress and long continuance.

Of long standing; slow and continued.

Lasting a long time; enduring.

Relating to time; of long continuance. A chronic disease, one which is inveterate, or of long continuance, in distinction from an acute.

Of long duration.

Not acute; long-continued.

Lingering, of long duration; lasting a long time, in opposition to acute. [Gr.]