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Synonyms

sac

1 American  
[sak] / sæk /

noun

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

Sac 2 American  
[sak, sawk] / sæk, sɔk /

noun

plural

Sacs,

plural

Sac

  1. Sauk.

SAC 3 American  
[sak] / sæk /
Or S.A.C.

noun

  1. Strategic Air Command.

sac 1 British  
/ sæk /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
SAC 2 British  

abbreviation

  1. Special Area of Conservation

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
sac Scientific  
/ săk /

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

Other Word Forms

  • saclike adjective

Etymology

Origin of sac

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

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.

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

“It’s quality at-bats, quality outs, moving guys over, getting sac flies, bringing defenses in if you move them over,” Freeman said.

From Los Angeles Times • Sep. 14, 2025

Knee and ankle issues began in 2017, then two years later she needed treatment for pericarditis - an inflammation of the fluid-filled sac around the heart - which was potentially career-ending.

From BBC • Jun. 4, 2025

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

Then Templeton bared his long ugly teeth and began snipping the threads that fastened the sac to the ceiling.

From "Charlotte's Web" by E.B. White

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.