nucleolus

noun
nu·​cle·​o·​lus | \ nü-ˈklē-ə-ləs How to pronounce nucleolus (audio) , nyü- \
plural nucleoli\ nü-​ˈklē-​ə-​ˌlī How to pronounce nucleolus (audio) , nyü-​ \

Definition of nucleolus

: 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

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Other Words from nucleolus

nucleolar \ nü-​ˈklē-​ə-​lər How to pronounce nucleolus (audio) , nyü-​ \ adjective

Examples of nucleolus in a Sentence

Recent Examples on the Web 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, "Sloppy science or groundbreaking idea? Theory for how cells organize contents divides biologists," 21 Jan. 2021 More membraneless structures continued to be found, such as the nucleolus, a dense structure in the cell nucleus. Quanta Magazine, "‘Lava-Lamp’ Proteins May Help Cells Cheat Death," 26 Nov. 2018 But there’s more to the nucleolus than just making ribosomes. Joanna Klein, New York Times, "The Thing Inside Your Cells That Might Determine How Long You Live," 20 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nucleolus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of nucleolus

1839, in the meaning defined above

History and Etymology for nucleolus

New Latin, from Latin, diminutive of nucleus

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Time Traveler for nucleolus

Time Traveler

The first known use of nucleolus was in 1839

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Statistics for nucleolus

Last Updated

29 Jan 2021

Cite this Entry

“Nucleolus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nucleolus. Accessed 25 Feb. 2021.

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More Definitions for nucleolus

nucleolus

noun
nu·​cle·​o·​lus | \ n(y)ü-ˈklē-ə-ləs How to pronounce nucleolus (audio) \
plural nucleoli\ -​ˌlī How to pronounce nucleolus (audio) \

Medical Definition of nucleolus

: 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

More from Merriam-Webster on nucleolus

Britannica.com: Encyclopedia article about nucleolus

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