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air s's (alveolar s's) the spaces into which the alveolar ducts open distally, and with which the alveoli communicate; see also lung.
amniotic sac the sac formed by the amnion, enclosing the fetus suspended in amniotic fluid; popularly known as the bag of waters.
conjunctival sac the potential space, lined by conjunctiva, between the eyelids and the eyeball.
endolymphatic sac the blind, flattened cerebral end of the endolymphatic duct.
hernial sac the peritoneal pouch that encloses protruding intestine.
lacrimal sac the dilated upper end of the nasolacrimal duct; see also lacrimal apparatus.
yolk sac the extraembryonic membrane connected with the midgut; in vertebrates below true mammals, it contains a yolk mass.
the protruding envelope of peritoneum in a hernia.
Etymology: L, hernia, rupture; Gk, sakkos, sack
a pouch of peritoneum into which organs or other tissues pass to form a hernia.
her·ni·al sac(hĕr'nē-ăl sak)
The peritoneal envelope of a hernia.
hernial sacA bag of PERITONEUM pushed through a hernial orifice and containing the loop of bowel or other body part that has herniated.
a pouch; a baglike organ or structure. See also conjunctival sac.
1. alveolar sac.
2. one of the large air-filled diverticula of the respiratory system of birds. See also air sacs.
the spaces into which the alveolar ducts open distally, and with which the alveoli communicate.
see anal sacs.
the blind, flattened cerebral end of the endolymphatic duct.
the peritoneal pouch that encloses a herniated viscus or mesentery.
see lacrimal sac.
see anal sacs.
the pleura-lined cavity which contains the lung.
one of the dorsal and ventral sacs of the rumen which are themselves further subdivided to create a caudodorsal sac and a caudoventral sac.
the extraembryonic membrane connected with the midgut; in vertebrates other than true mammals, it contains a yolk mass. See also yolk sac.