macronucleus

noun
mac·​ro·​nu·​cle·​us | \ ˌma-krō-ˈnü-klē-əs How to pronounce macronucleus (audio) , -ˈnyü- \

Definition of macronucleus

: a relatively large densely staining nucleus of most ciliate protozoans that is derived from micronuclei and controls various nonreproductive functions

Other Words from macronucleus

macronuclear \ ˌmak-​rō-​ˈnü-​klē-​ər How to pronounce macronucleus (audio) , -​ˈnyü-​ , nonstandard  -​kyə-​lər \ adjective

First Known Use of macronucleus

1887, in the meaning defined above

History and Etymology for macronucleus

macro- + nucleus

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Time Traveler for macronucleus

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The first known use of macronucleus was in 1887

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Dictionary Entries Near macronucleus

macronucleate

macronucleus

macronutrient

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Cite this Entry

“Macronucleus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/macronucleus. Accessed 20 May. 2022.

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More Definitions for macronucleus

macronucleus

noun
mac·​ro·​nu·​cle·​us | \ ˌmak-rō-ˈn(y)ü-klē-əs How to pronounce macronucleus (audio) \
plural macronuclei\ -​ˌī How to pronounce macronucleus (audio) \ also macronucleuses

Medical Definition of macronucleus

: a relatively large densely staining nucleus of most ciliate protozoans that is derived from micronuclei and controls various nonreproductive functions — compare micronucleus

Other Words from macronucleus

macronuclear \ ˌmak-​rō-​ˈn(y)ü-​klē-​ər How to pronounce macronucleus (audio) \ adjective

More from Merriam-Webster on macronucleus

Britannica.com: Encyclopedia article about macronucleus

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