abdominal cavity, amniotic sac, pericardium, pericardial sac, uterine cavity, pus, bursa, chest cavity, intestines, alveoli, parenchyma, pelvic cavity, bronchi, rib cage, fibrous tissue, cysts, capillaries, gland, oviduct, fibroid tumor, bronchioles, fallopian tube, meninges, spinal canal, yolk sac, vas deferens, udder, fibrocartilage, inferior vena cava, calyx, papilla, embolus, nasal cavity, cartilages, umbilicus, fontanelle, bronchial tubes, abdomen, spinal column, cannula, pulmonary valve, fatty tissue, urethra, conjunctiva, thoracic cavity, trachea, sheath, periosteum, pannus, fossa, epicardium, pouch, trabeculae, diverticula, amniotic cavity, spermatic cord, epididymis, amnion, abdominal wall, peritoneal cavity, bronchial tube, aorta, gill, ovary, uterus, arterioles, omentum, testes, bleb, ostium, iliac artery, epithelium, papule, sulci, integument, intima, windpipe, ectopic, cloaca, tubules, lobules, ureter, diaphragm, whitehead, vena cava, thyroid cartilage, vesicle, epiglottis, aspirate, parathyroid gland, uterine artery, subarachnoid space, pleural cavity, medulla, mesentery, duodenum, midgut, perineum, inguinal canal, lungs, epiphysis, breastbone, sacs, cavity, auricle, capsule, nostril, siphon, ampulla, cavities, cranium, meatus, appendage, canal, cord, diverticulum, allantoic, cyst, embryonic, mesonephric, embryonal, sebaceous, alveolar, endodermal, extraembryonic, lacunar, nasopharyngeal, thecal, bursal, caecal, cell, sinus, amniotic, aneurysmal, antral, endolymphatic

acinus, air bladder, air cell, air sac, allantois, alveolus, bladder, bursa, cistern, cisterna, coelenteron, cyst, pericardial sac, pocket, pouch, saccule, sacculus, swim bladder, vesica, vesicle, yolk sac

., air bladder, air cell, air sac, alveolus, amnion, amnios, amniotic sac, aneurism, aneurysm, ascomycetes, ascomycota, ascomycotina, bladder, bladdernose, bursa, capsular, chorion, cistern, cisterna, class ascomycetes, cyst, cystophora cristata, dacryocystitis, enucleate, gallbladder, geastrum coronatum, hooded seal, hydrocele, induction of labor, meckel's diverticulum, meningocele, microspore, myelomeningocele, nasolacrimal duct, nucellus, order pulmonata, perisperm, pulmonata, rudiment, saccule, sacculus, sac fungus, subdivision ascomycota, subdivision ascomycotina, swim bladder, theca, urinary bladder, urocele, vascularize, vesica, vesicle, vitelline circulation

bodily cavity, cavity, cavum, cover, covering, enclosed space, natural covering

pocket, pouch, sack, theca