Definition

1. Noun:
   • A bag-like structure in a plant or animal: A sac is a part of an organism that is shaped like a pouch or bag and often contains fluid, air, or another substance.
   • An enclosed space or cavity: A sac can refer to any enclosed or confined area, often containing a specific substance like air or fluid.
   • (Capitalized) A member of a Native American people: When capitalized ("Sac"), it refers to a person belonging to the Algonquian people historically living in parts of what is now the Midwestern United States.

Examples of Usage

• Noun (Biological Structure):
  • The pollen sac of the flower burst open.
  • Air sacs in the lungs are crucial for respiration.
• Noun (Enclosed Space):
  • The geode had a small sac filled with crystals.
  • They discovered a sac of air in the cave.
• Noun (Ethnic Group):
  • The Sac and Fox tribes were relocated in the 19th century.

Advanced Usage

• "embryonic sac": In biology, the structure that surrounds and protects an embryo.
  • The embryonic sac provides nutrients to the developing fetus.
• "lacrimal sac": In anatomy, the tear-draining sac in the inner corner of the eye.
  • A blocked lacrimal sac can cause excessive tearing.

Variants and Related Words

• Saccate (adj): Having the form of a sac or pouch.
  • The saccate organ stores digestive enzymes.
• Saccule (n): A small sac, especially within the vestibular system of the ear.
  • The saccule helps with balance.

Synonyms

• Pouch: A small bag or sack-like structure.
• Cyst: A closed sac in the body that may contain fluid or semi-solid material (often pathological).
• Vesicle: A small fluid-filled sac or blister.

Related Phrases

• Yolk sac: The membranous sac attached to an embryo, providing early nourishment.
  • The yolk sac is an important source of nutrition for bird and reptile embryos.
• Amniotic sac: The fluid-filled sac that cushions the fetus during pregnancy.
  • The amniotic sac ruptured, signaling the start of labor.

Noun

1. a structure resembling a bag in an animal
2. a member of the Algonquian people formerly living in Wisconsin in the Fox River valley and on the shores of Green Bay
3. a case or sheath especially a pollen sac or moss capsule
4. an enclosed space
   • the trapped miners found a pocket of air