lysosome

American  

[lahy-suh-sohm] / ˈlaɪ səˌsoʊm /

noun

Cell Biology.

1. a cell organelle containing enzymes that digest particles and that disintegrate the cell after its death.

---

lysosome British  

/ ˈlaɪsəˌsəʊm /

noun

1. any of numerous small particles, containing digestive enzymes, that are present in the cytoplasm of most cells

---

lysosome Scientific  

/ lī′sə-sōm′ /

1. A cell organelle that is surrounded by a membrane, has an acidic interior, and contains hydrolytic enzymes that break down food molecules, especially proteins and other complex molecules. Lysosomes fuse with vacuoles to digest their contents. The digested material is then transported across the organelle's membrane for use in or transport out of the cell.

2. See more at cell

---

Other Word Forms

Derived Forms

• lysosomal
  adjective

Etymology

Origin of lysosome

First recorded in 1950–55; lyso- + -some ³

Explanation

In biology, a lysosome is an organelle that contains digestive enzymes and is wrapped in a membrane. Lysosomes act as a sort of digestive system for cells. The job of a lysosome is to get rid of cell parts that are old or unneeded — basically, to break down and clear away any waste products. If the cell itself is too damaged to function properly, a lysosome can also help to break down the entire cell, a process called "programmed cell death." The word lysosome was coined in 1955, from roots meaning "loosening" and "the body," to give a sense of their digestive properties.

Example Sentences

The results showed a significant reduction in the activity of genes linked to lysosome function.

From Science Daily • Nov. 7, 2025

More importantly, they demonstrated that stimulating lysosome activity can restore this cellular "cleanup" function, helping remove progerin and reducing signs of cell aging.

From Science Daily • Nov. 7, 2025

Another key protein, progranulin, regulates cell growth and a part of the cell called the lysosome that breaks down cellular waste products.

From Salon • Feb. 26, 2023

After phagocytosis by APCs, the phagocytic vesicle fuses with an intracellular lysosome forming phagolysosome.

From Textbooks • Jun. 9, 2022

This vesicle then fuses with a lysosome, and the food particle is broken down into small molecules that can diffuse into the cytoplasm and be used in cellular metabolism.

From Textbooks • Apr. 25, 2013