nucleoid
Americannoun
adjective
Usage
What is a nucleoid? A nucleoid is the central part of a prokaryotic cell that contains genetic material. A nucleoid is found only in a prokaryotic cell, such as a single-celled bacteria. It’s integral to reproduction and genetic behavior, housing chromosomes and DNA and, in some prokaryotic cells, additional DNA called plasmids. RNA and proteins can also be found within the nucleoid area. Nucleoid can be used to describe something that resembles a nucleus (a specialized mass of protoplasm encased in a double membrane). Example: If you examine the nucleoid of the bacteria, you’ll see that it lacks a specific chromosome related to that gene in similar organisms.
Etymology
Origin of nucleoid
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Most of these bead-like sections contain a nucleoid near the center, although the structures can also form without mtDNA present.
From Science Daily ● Apr. 13, 2026
They have a single piece of circular DNA in the nucleoid area of the cell.
From Textbooks ● Jun. 9, 2022
It has a cell wall enclosing nuclear membrane, cytoplasm, mitochondria, vacuoles and nucleoid region with genetic material.
From Textbooks ● Jun. 9, 2022
They typically have cell walls enclosing nuclear membranes, cytoplasm, ribosomes, mitochondria and nucleoid region with genetic material.
From Textbooks ● Jun. 9, 2022
It has a cell wall enclosing nuclear membrane, cytoplasm, ribosomes and nucleoid region with genetic material.
From Textbooks ● Jun. 9, 2022
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
