ductwork, ventilation, vents, pipework, coils, peritoneal cavity, airflow, pipes, radiators, tubes, condenser, downpipe, flue pipe, membranes, flues, louvres, wiring, tubules, inferior vena cava, louvers, soffits, cavity, bronchioles, lobules, underfloor, crawlspace, firebox, subfloor, intercooler, lymphatics, abdominal cavity, ventilating, mains, pores, spiracles, bronchi, upflow, convector, sumps, glands, pleural cavity, stopcock, capillaries, hose, dehumidifying, bronchial tubes, venturi, anal canal, heat exchanger, insulation, spermatic cord, cabling, passageways, plenums, floor joist, laminar flow, orifices, vas deferens, humidistat, trachea, gutters, impellers, fallopian tube, crossflow, flashings, epithelium, exhaust pipe, inlet manifold, cryostat, ascending aorta, ostia, medullary, capillary tubing, fittings, intestines, penstock, hoistway, alveoli, exhaust manifold, peltier, valve, plumbing, pleural, thoracic duct, radiant heat, diaphragm, weatherstrip, breezeways, manway, firebrick, uterine, iliac artery, nozzles, epididymis, apertures, gaskets, auditory canal, superheater, bleb, urethra, amniotic sac, linings, duct, canaliculi, canals, ductules, acini, fissures, loops, lumina, tubular, bundles, capillary

angiopathy, bilestone, bile duct, biliary, biliary ductule, block, bronchiole, calculus, cholangiography, cholangitis, common bile duct, concretion, cylinder block, dacryocyst, digestive gland, engine block, fasciola hepatica, gallstone, gland, heat rash, hepatic, hilum, hilus, lachrymal duct, lacrimal bone, lacrimal duct, lacrimal sac, lactiferous duct, liver fluke, miliaria, prickly heat, secreter, secretor, secretory organ, tear duct, tear sac