metaproterenol: a bronchodilator (trade name Alupent) used to treat asthma and emphysema and other lung conditions; available in oral or inhalant forms; side effects include tachycardia and shakiness
bronchodilator: a drug that relaxes and dilates the bronchial passageways and improves the passages of air into the lungs
screen door: a door that consists of a frame holding metallic or plastic netting; used to allow ventilation and to keep insects from entering a building through the open door