What does "tubular" mean?

Tubular: Having the form of a tube, or pipe; consisting of a pipe; fistular; as, a tubular snout; a tubular calyx. Also, containing, or provided with, tubes. Tubular boiler. See under Boiler. -- Tubular breathing (Med.), a variety of respiratory sound, heard on auscultation over the lungs in certain cases of disease, resembling that produced by the air passing through the trachea. -- Tubular bridge, a bridge in the form of a hollow trunk or tube, made of iron plates riveted together, as the Victoria bridge over the St. Lawrence, at Montreal, Canada, and the Britannia bridge over the Menai Straits. -- Tubular girder, a plate girder having two or more vertical webs with a space between them.