ribosome

American  

[rahy-buh-sohm] / ˈraɪ bəˌsoʊm /

noun

Cell Biology.

1. a tiny, somewhat mitten-shaped organelle occurring in great numbers in the cell cytoplasm either freely, in small clusters, or attached to the outer surfaces of endoplasmic reticula, and functioning as the site of protein manufacture.

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ribosome British  

/ ˈraɪbəˌsəʊm /

noun

1. any of numerous minute particles in the cytoplasm of cells, either free or attached to the endoplasmic reticulum, that contain RNA and protein and are the site of protein synthesis

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ribosome Scientific  

/ rī′bə-sōm′ /

1. A sphere-shaped structure within the cytoplasm of a cell that is composed of RNA and protein and is the site of protein synthesis. Ribosomes are free in the cytoplasm and often attached to the membrane of the endoplasmic reticulum. Ribosomes exist in both eukaryotic and prokaryotic cells. Plastids and mitochondria in eukaryotic cells have smaller ribosomes similar to those of prokaryotes.

2. See more at cell

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ribosome Cultural  

1. A small, ball-like structure in the cell, made of proteins and RNA molecules, that serves as a platform on which the cell's proteins are made.

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Other Word Forms

• ribosomal adjective

Etymology

Origin of ribosome

First recorded in 1955–60; ribo(se) + -some ³

Example Sentences

By combining biochemical experiments with cryo-electron microscopy, the research group demonstrated that ribosome collisions serve as the main activation cue for ZAK.

From Science Daily • Nov. 25, 2025

Ribosomal RNA is often modified with chemical tags that can alter the shape and function of the ribosome.

From Science Daily • Nov. 29, 2024

Traditionally, antibiotics have targeted the ribosome or RNAP, but bacteria often find a way to evolve and mutate to create some resistance to those antibiotics.

From Science Daily • Nov. 28, 2024

This group didn’t conduct experiments of its own, but plumbed what others had done, first combing through ribosome profiling papers.

From Science Magazine • Nov. 24, 2024

Proteins, Brenner and Jacob knew, are synthesized within a cell by a specialized cellular component called the ribosome.

From "The Gene" by Siddhartha Mukherjee