sac

¹ American  

[sak] / sæk /

noun

1. a baglike structure in an animal, plant, or fungus, as one containing fluid.

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Sac ² American  

[sak, sawk] / sæk, sɔk /

noun

plural

Sacs,

plural

Sac

1. Sauk.

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SAC ³ American  

[sak] / sæk /

Or S.A.C.

noun

1. Strategic Air Command.

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SAC ¹ British  

abbreviation

1. Special Area of Conservation

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sac ² British  

/ sæk /

noun

1. a pouch, bag, or pouchlike part in an animal or plant

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sac Scientific  

/ săk /

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

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Other Word Forms

• saclike adjective

Etymology

Origin of sac

First recorded in 1735–45; from Latin saccus “bag, sackcloth”; sack ¹

Example Sentences

Meanwhile, the cul de sac, a street design much in favor with the architects of suburban developments, have become artificial catchments for these highly flammable weeds.

From The Wall Street Journal • Nov. 17, 2025

The next day she was diagnosed with pericarditis - an inflammation of the fluid-filled sac around the heart.

From BBC • Oct. 12, 2025

At the hospital, Nusslock said she was diagnosed with a premature rupture of the membrane of the amniotic sac — a dangerous complication in which an abortion is a recommended treatment.

From Los Angeles Times • Sep. 30, 2024

A sac fly from Kendle in the fourth and a run-scoring groundout by Woody Hadeen pushed the Irvine advantage to 6-2.

From Seattle Times • Jun. 2, 2024

The torn edges of the artery's walls formed a bulging sac that held in blood flowing through the vessel.

From "Ambushed!" by Gail Jarrow

Related Words

• cyst