amitosis

noun

ami·​to·​sis ˌā-mī-ˈtō-səs How to pronounce amitosis (audio)
: cell division by simple cleavage of the nucleus and division of the cytoplasm without spindle formation or appearance of chromosomes
amitotic
ˌā-mī-ˈtä-tik How to pronounce amitosis (audio)
adjective
amitotically
ˌā-mī-ˈtä-ti-k(ə-)lē How to pronounce amitosis (audio)
adverb

Word History

Etymology

a- entry 2 + mitosis, after amitotic, borrowed from German amitotisch

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of amitosis was in 1888

Rhymes for amitosis

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Browse Nearby Words

amitate
amitosis
amitotic
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Cite this Entry

“Amitosis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amitosis. Accessed 7 Jul. 2026.

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Medical Definition

amitosis

noun
ami·​to·​sis ˌā-mī-ˈtō-səs How to pronounce amitosis (audio)
plural amitoses -ˌsēz How to pronounce amitosis (audio)
: cell division by simple cleavage of the nucleus and division of the cytoplasm without spindle formation or appearance of chromosomes

called also direct cell division

amitotic
-ˈtät-ik How to pronounce amitosis (audio)
adjective
amitotically
-i-k(ə-)lē How to pronounce amitosis (audio)
adverb
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