aspen: any of several trees of the genus Populus having leaves on flattened stalks so that they flutter in the lightest wind
poplar: any of numerous trees of north temperate regions having light soft wood and flowers borne in catkins
albuterol: a bronchodilator (trade names Ventolin or Proventil) used for asthma and emphysema and other lung conditions; available in oral or inhalant forms; side effects are tachycardia and shakiness