a drug that relaxes and dilates the bronchial passageways and improves the passages of air into the lungs
bronchodilator详细解释
bron.cho.di.la.tor n.（名词）A drug that widens the air passages of the lungs and eases breathing by relaxing bronchial smooth muscle.支气管扩张剂：一种可加宽肺里空气通道的药物，并通过放松支气管的平滑肌来使呼吸轻松
