Final answer:
Bronchial asthma is defined as a chronic inflammatory condition of the respiratory passages that causes coughing and excessive mucus production, differentiating it from other similar pulmonary diseases.
Step-by-step explanation:
Bronchial asthma is chronic dilation of respiratory passages causing tussis (cough) and excessive mucus production. Asthma is a chronic inflammatory disease of the airways in the lungs, leading to symptoms like difficulty breathing, coughing, wheezing, chest tightness, and excessive mucus production. Occasionally, pulmonary diseases such as cystic fibrosis and emphysema may also cause similar symptoms, but they have different etiologies and mechanisms compared to asthma.