vesicle

American  

[ves-i-kuhl] / ˈvɛs ɪ kəl /

noun

1. a small sac or cyst.

2. Biology. a small bladderlike cavity, especially one filled with fluid.

3. Pathology. a circumscribed elevation of the epidermis containing serous fluid; blister.

4. Geology. a small, usually spherical cavity in a rock or mineral, formed by expansion of a gas or vapor before the enclosing body solidified.

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vesicle British  

/ vɛˈsɪkjʊlə, ˈvɛsɪkəl /

noun

1. pathol

   1. any small sac or cavity, esp one containing serous fluid

   2. a blister

2. geology a rounded cavity within a rock formed during solidification by expansion of the gases present in the magma

3. botany a small bladder-like cavity occurring in certain seaweeds and aquatic plants

4. any small cavity or cell

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vesicle Scientific  

/ vĕs′ĭ-kəl /

1. A small fluid-filled sac in the body.

2. A membrane-bound sac in eukaryotic cells that stores or transports the products of metabolism in the cell and is sometimes the site for the breaking down of metabolic wastes. Vesicles bulge out and break off from the endoplasmic reticulum and the Golgi apparatus. Vesicles get their energy for mobility from ATP. Lysosomes and peroxisomes are vesicles.

3. A small cavity formed in volcanic rock by entrapment of a gas bubble during solidification.

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Other Word Forms

• vesicular
  adjective
• vesicularly
  adverb

Etymology

Origin of vesicle

First recorded in 1570–80, vesicle is from the Latin word vēsīcula little bladder. See vesica, -ule

Explanation

A vesicle is a tiny cavity or sac in an animal, even a human animal. Vesicles are like bladders or blisters, and they usually hold fluid. They’re really small. Vesicle is from the Latin word vesicular for “bladder or blister.” A vesicle is like a little bladder, because it's a fluid-filled sac in an animal, like little organic bags of liquid. The other key element of a vesicle is that it's small — vesicles tend to be extremely tiny. They’re so small, that some are inside cells, as membrane-bound spheres that are separate from the surrounding cytoplasm. That’s tiny!

Example Sentences

See Examples For:

vesicle

As the pocket expands, it wraps around the virus and forms a vesicle.

From Science Daily ● Dec. 4, 2025

When the team applied zap-and-freeze to the human tissue samples, they found the same vesicle recycling steps occurring in human neurons.

From Science Daily ● Dec. 1, 2025

Specifically, those that involve dysfunction in synaptic vesicle recycling and neurotransmission, says Kravčenko.

From Science Daily ● Dec. 3, 2024

The vesicle fuses with a lysosome, and proteins inside the lysosome digest the food particle.

From Textbooks ● Jan. 1, 2015

A membranous appendage of the embryos of mammals, birds, and reptiles, Ð in mammals serving to connect the fetus with the parent; the urinary vesicle.

From Webster's Unabridged Dictionary by Webster, Noah