Sac (redirected from alveolar sacs)

Sac  (sk, sôk)

n.

Variant of Sauk.

---

sac  (sk)

n.

A pouch or pouchlike structure in a plant or an animal, sometimes filled with fluid.

---

[French, bag, from Old French, from Latin saccus; see sack¹.]

---

sac

Noun

a pouch or pouchlike part in an animal or plant [Latin saccus]

---

sac  (sk)

A pouch or pouch-shaped structure in an animal or plant, often containing liquids. The human bladder is a sac.

Thesaurus

Noun	1.	sac - an enclosed space; "the trapped miners found a pocket of air" pocket, pouch, sack enclosed space, cavity - space that is surrounded by something
	2.	sac - a case or sheath especially a pollen sac or moss capsule theca covering, natural covering, cover - a natural object that covers or envelops; "under a covering of dust"; "the fox was flushed from its cover"
	3.	Sac - a member of the Algonquian people formerly living in Wisconsin in the Fox River valley and on the shores of Green Bay Sauk Algonquian, Algonquin - a member of any of the North American Indian groups speaking an Algonquian language and originally living in the subarctic regions of eastern Canada; many Algonquian tribes migrated south into the woodlands from the Mississippi River to the Atlantic coast
	4.	sac - a structure resembling a bag in an animal yolk sac - membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo umbilical vesicle, vesicula umbilicus, vitelline sac, yolk sac - membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional amnion, amnios, amniotic sac - thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals) chorion - the outermost membranous sac enclosing the embryo in higher vertebrates (reptiles, birds and mammals) coelenteron - the saclike body cavity of a coelenterate air bladder, swim bladder, float - an air-filled sac near the spinal column in many fishes that helps maintain buoyancy air sac - any of the membranous air-filled extensions of the lungs of birds air sac - any of the thin-walled extensions of the tracheae of insects bodily cavity, cavum, cavity - (anatomy) a natural hollow or sinus within the body saccule, sacculus - a small sac or pouch (especially the smaller chamber of the membranous labyrinth) bladder, vesica - a distensible membranous sac (usually containing liquid or gas) acinus - one of the small sacs or saclike dilations in a compound gland bursa - a small fluid-filled sac located between movable parts of the body especially at joints cistern, cisterna - a sac or cavity containing fluid especially lymph or cerebrospinal fluid pouch, pocket - (anatomy) saclike structure in any of various animals (as a marsupial or gopher or pelican) vesicle, cyst - a small anatomically normal sac or bladderlike structure (especially one containing fluid) air cell, air sac, alveolus - a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways pericardial sac - the membrane surrounding the heart

---

sac

noun pouch, bag, pocket, bladder, pod, cyst, vesicle