sac
noun
a baglike structure in an animal, plant, or fungus, as one containing fluid.
Showing results for "sac"
- a variation of Sauk.
sac
1 American
[sak]
/ sæk /
noun
-
sacs
plural
Sac
2
American
[sak, sawk]
/ sæk, sɔk /
noun
-
Sacs,
plural
-
Sac
plural
SAC
3
American
[sak]
/ sæk /
Or
S.A.C.
noun
sac
1
British
/ sæk /
noun
SAC
2
British
abbreviation
sac
Scientific
/ săk /
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of sac
First recorded in 1735–45; from Latin saccus “bag, sackcloth”; see sack 1
Explanation
A sac is a hollow space or container. While any pocket or pouch can be called a sac, the word usually refers to a small enclosed space that occurs in nature, like a spider's egg sac or a squid's ink sac. You might put your groceries in a sack, but without the “k” a sac is smaller and attached to a plant or animal. Human fetuses grow inside an amniotic sac, and seed plants produce pollen inside sacs as well. Since the mid-1700s, sac has been used to mean "biological pocket," from the Latin root word saccus, or "bag." If you’re not sure which sac to use, it’s almost always the other one unless you’re in biology class.
Vocabulary lists containing sac
Commonly Confused Words, List 4
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Unit 2: Evolution
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The Benefits of Being an Octopus
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
The larvae can alter the pH of the sac walls, causing the resilin to expand or contract.
From Science Daily ● Jul. 27, 2026
Froome's wife later said doctors discovered a pericardial rupture - an injury where the sac that surrounds the heart is torn - during surgery and were able to repair it.
From BBC ● Jul. 3, 2026
In a dark room, a doctor pointed to an hourglass shape glowing on the ultrasound screen: There was her amniotic sac, funneling into her dilated cervix, and there was their tiny daughter’s foot, dipping out.
From Salon ● May 27, 2026
Then came the worst part: I passed the amniotic sac.
From The Wall Street Journal ● May 13, 2026
In their report, the doctors blamed Garfield's death on the bursting of this sac.
From "Ambushed!" by Gail Jarrow
In nearby Sac City, Crystal Hanrahan was watching the case unfold when she got an idea.
From The Wall Street Journal ● Nov. 26, 2025
"We've got to flush this one down the toilet and get ready for Sac," said Kerr, whose side face the Sacramento Kings in their next match.
From BBC ● Jan. 21, 2025
Boys and girls cross country qualify for CIF Finals next Saturday at My Sac.
From Los Angeles Times ● Nov. 17, 2024
The last bank failure — Citizens Bank, based in Sac City, Iowa — was in November.
From Seattle Times ● Apr. 26, 2024
“Omaha, Nebraska. Sac City, Iowa. Alexandria, Indiana. Darwin, Minnesota. Hollywood, California. Alliance, Nebraska. Okay. Those are the locations of all the things she—well, or whoever read this book—found interesting.”
From "Paper Towns" by John Green
Defra says it may not be necessary to make this area of maerl beds an SAC, "nor is there a requirement, to protect all examples of a species or habitats."
From BBC ● Jul. 31, 2026
At Mount SAC, for instance, classrooms have high-tech mannequins that can be programmed to blink, shriek and simulate a variety of medical conditions, including heart attacks, bleeding, respiratory failure — even giving birth.
From Los Angeles Times ● Oct. 6, 2025
Mount SAC, for instance, lost placements at multiple sites.
From Los Angeles Times ● Oct. 6, 2025
The situation has already led to limits being placed on housebuilding along SAC rivers.
From BBC ● Jun. 24, 2025
The red phone put him in direct touch with SAC wings all over the globe.
From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin
The Sacs and Fox mined and smelted 60 tons of lead for Shreve.
From Time Magazine Archive
The Sacs and Foxes made a treaty with the United States in 1830, by which they ceded all their lands in Illinois to the government.
From The Greater Republic A History of the United States by Charles Morris
They were at war with many surrounding nations, and, among the rest, with the Sacs and Foxes, who often brought their prisoners to the French settlements for sale.
From The Conspiracy of Pontiac and the Indian War after the Conquest of Canada by Francis Parkman
Black Hawk came, and with him a host of tributary chiefs—Shawnees, Blackfeet, Sacs and Foxes, etc.
From Adventures Among the Red Indians Romantic Incidents and Perils Amongst the Indians of North and South America by H. W. G. Hyrst
One time, visiting a winter camp of the Sacs and Foxes, far from their permanent village, we saw a strange bundle in a tree.
From American Indians by Frederick Starr
These sacs act much like the ballast tanks of a submarine.
From Science Daily ● Jul. 27, 2026
Caitlin and Grace had been believed to be fraternal twins because they developed in different amniotic sacs, but doctors found their markers were exactly the same while assessing Grace as a potential stem cell donor.
From BBC ● Jul. 1, 2026
In another chapter, Mr. Haskell follows the path of an owlet moth into the cranefly orchid’s flower and lets us watch how sacs of pollen attach themselves to the insect’s eye.
From The Wall Street Journal ● Apr. 17, 2026
The spiders’ white egg sacs, usually laid between October and November, are often attached to leaves, tree bark and flat structures and contain 400 to 500 eggs, according to Jorowatch.
From Los Angeles Times ● Apr. 9, 2026
The poison sacs of the town began to manufacture venom, and the town swelled and puffed with the pressure of it.
From "The Pearl" by John Steinbeck
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
