nucleolus
noun
nu·cle·o·lus nü-ˈklē-ə-ləs 
nyü-
plural nucleoli nü-ˈklē-ə-ˌlī
nyü-
: a spherical body of the nucleus of most eukaryotes that becomes enlarged during protein synthesis, is associated with a nucleolus organizer, and contains the DNA templates for ribosomal RNA
see cell illustration
Examples of nucleolus in a Sentence
Recent Examples on the Web
But at the time Wagner and Valentin had little idea of the nucleolus’s function. —
Trevor Grandpre, Scientific American, 14 Aug. 2024 In 2012, Brangwynne and colleagues saw similar fluid features in the nucleolus, a dense mix of proteins, RNA, and DNA that manufactures ribosomes, the cell’s protein factories. —Mitch Leslie, Science | AAAS, 21 Jan. 2021 More membraneless structures continued to be found, such as the nucleolus, a dense structure in the cell nucleus. —Quanta Magazine, 26 Nov. 2018 But there’s more to the nucleolus than just making ribosomes. —Joanna Klein, New York Times, 20 May 2018
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Trevor Grandpre, Scientific American, 14 Aug. 2024 In 2012, Brangwynne and colleagues saw similar fluid features in the nucleolus, a dense mix of proteins, RNA, and DNA that manufactures ribosomes, the cell’s protein factories. —Mitch Leslie, Science | AAAS, 21 Jan. 2021 More membraneless structures continued to be found, such as the nucleolus, a dense structure in the cell nucleus. —Quanta Magazine, 26 Nov. 2018 But there’s more to the nucleolus than just making ribosomes. —Joanna Klein, New York Times, 20 May 2018
Cite this Entry
“Nucleolus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.grautoblog.com/dictionary/nucleolus. Accessed 29 Apr. 2026.
Copy CitationKids Definition
nucleolus
noun
nu·cle·o·lus n(y)ü-ˈklē-ə-ləs
plural nucleoli -ˌlī
: a sphere-shaped body in the cell nucleus that is associated with a particular part of a chromosome, and is rich in ribosomal RNA
Medical Definition
nucleolus
noun
nu·cle·o·lus n(y)ü-ˈklē-ə-ləs
plural nucleoli -ˌlī
: a spherical body of the nucleus of most eukaryotes that becomes enlarged during protein synthesis, is associated with a nucleolus organizer, and contains the DNA templates for ribosomal RNA
called also plasmosome
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