chronic bronchitis
Medical term for a long-term inflammation of the bronchial tubes.
Smoking is one of the main causes of chronic bronchitis.
彼は慢性気管支炎と診断された。
He was diagnosed with chronic bronchitis.
ＣＢ is a clinical shorthand, while 慢性気管支炎 is the full medical term for chronic bronchitis.
Compound of 慢性 (chronic) and 気管支炎 (bronchitis). The term is a direct medical compound with no irregular etymology.