noun
Uncommon
sac
sak
Sac (noun) means a pouch-like structure in a plant or animal, usually containing fluid. Example: “The venom sac sits just behind the snake's fangs.”
noun
1
A pouch-like structure in a plant or animal, usually containing fluid.
"The venom sac sits just behind the snake's fangs."
"A yolk sac supplies nutrients to the developing embryo."
"The spider wrapped her eggs in a silky sac."
How to use sac
Learner’s notesIn plain EnglishA small bag-like pouch inside a living thing, usually holding liquid.
Common mistake
Not to be confused with "sack," a bag for carrying goods — "sac" is the biological term.
Easily confused with
Common pairings
venom sac
yolk sac
air sac
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Word forms
- Plural
- sacs
- Third person singular
- sacs
- Past tense
- sacked, sacced
Fill the gap
Can you complete this real example?
The venom _____ sits just behind the snake's fangs.
Etymology
From Latin saccus ("bag"), the same root that gives us "sack."
Related words
Frequently asked questions
What does “sac” mean?
The word “sac” means a pouch-like structure in a plant or animal, usually containing fluid. In plain terms, a small bag-like pouch inside a living thing, usually holding liquid.
How do you pronounce “sac”?
“Sac” is pronounced sak (/sæk/ in IPA).
How do you use “sac” in a sentence?
Here is “sac” used in a sentence: “The venom sac sits just behind the snake's fangs.”
What part of speech is “sac”?
“Sac” is a noun.
Where does the word “sac” come from?
The word “sac” comes from Latin. From Latin saccus ("bag"), the same root that gives us "sack.".
Is “sac” a common word?
“Sac” is an uncommon word in modern English.
What is the difference between a sac and a sack?
A sac is a pouch-like structure found in plants or animals, usually containing fluid, such as a yolk sac or amniotic sac, while a sack is a large bag used for carrying or storing dry goods. Despite the similar sound, sac is a biological term and sack refers to a container.
What are some examples of a 'sac' in biology?
Common examples include the amniotic sac surrounding a developing fetus, the yolk sac providing nutrients to an embryo, and various glandular sacs found in plants and animals that hold fluid. In each case, the sac is a pouch-like structure that contains and often protects its contents.
Is a sac the same as a cyst?
Not exactly. A sac is a general anatomical term for a pouch-like structure that usually contains fluid, while a cyst specifically refers to an abnormal fluid-filled sac that forms as a result of disease or injury. All cysts could be described as sacs, but not all sacs are cysts.
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