part of part of branching part of respiratory tube lung bronchiole EHDAA:8183 EMAPA:32697 The conducting airway of the lungs found terminal to the bronchi; these structures contain neither cartilage nor mucous-secreting glands; the epithelium of the bronchioles becomes thinner with each branching. In some texts/references/ontologies, bronchiole has been used as an exact synonym of 'lobular bronchiole'. However, a 'lobular bronchiole' is a segment of a bronchiole. bronchiolus VHOG:0000675 EHDAA:8221 EHDAA:8171 Wikipedia:Bronchiole UBERON:0002186 CALOHA:TS-2003 MA:0000422 bronchioli FMA:7410 EHDAA:8199 NCIT:C12684 SCTID:278982001 BTO:0002375 tracheobronchial tree