Noun

• S: (n) saccule, sacculus (a small sac or pouch (especially the smaller chamber of the membranous labyrinth))
• direct hypernym / inherited hypernym / sister term
• S: (n) sac (a structure resembling a bag in an animal)
• S: (n) yolk sac (membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo)
• S: (n) yolk sac, vitelline sac, umbilical vesicle, vesicula umbilicus (membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional)
• S: (n) amnion, amniotic sac, amnios (thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals))
• S: (n) chorion (the outermost membranous sac enclosing the embryo in higher vertebrates (reptiles, birds and mammals))
• S: (n) coelenteron (the saclike body cavity of a coelenterate)
• S: (n) air bladder, swim bladder, float (an air-filled sac near the spinal column in many fishes that helps maintain buoyancy)
• S: (n) air sac (any of the membranous air-filled extensions of the lungs of birds)
• S: (n) air sac (any of the thin-walled extensions of the tracheae of insects)
• S: (n) saccule, sacculus (a small sac or pouch (especially the smaller chamber of the membranous labyrinth))
• S: (n) bladder, vesica (a distensible membranous sac (usually containing liquid or gas))
• S: (n) acinus (one of the small sacs or saclike dilations in a compound gland)
• S: (n) bursa (a small fluid-filled sac located between movable parts of the body especially at joints)
• S: (n) cisterna, cistern (a sac or cavity containing fluid especially lymph or cerebrospinal fluid)
• S: (n) pouch, pocket ((anatomy) saclike structure in any of various animals (as a marsupial or gopher or pelican))
• S: (n) vesicle, cyst (a small anatomically normal sac or bladderlike structure (especially one containing fluid))
• S: (n) alveolus, air sac, air cell (a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways)
• S: (n) pericardial sac (the membrane surrounding the heart)
• part holonym
• S: (n) membranous labyrinth (the sensory structures of the inner ear including the labyrinthine receptors and the cochlea; contained within the bony labyrinth)
• part meronym
• direct hypernym / inherited hypernym / sister term
• part holonym