Context .- Bronchioloalveolar carcinoma is a term that has served lung pathology well for almost a century; however, more accurate terms have recently been suggested to better characterize the various lesions that have formerly all been considered bronchioloalveolar carcinoma. Objectives .- To evaluate the origin and history of the term bronchioloalveolar carcinoma and to compare the term's traditional uses with current understanding and terminology of lung lesions formerly termed bronchioloalveolar carcinoma. Data Sources .- Review of the literature pertaining to bronchioloalveolar carcinoma. Conclusions .- Bronchioloalveolar carcinoma has been an extremely useful term for many decades; however, it has now obtained respected obsolescence. Novel, more medically appropriate terms have been suggested for the group of lesions formerly termed bronchioloalveolar carcinoma, and these newer terms should now be routinely used.