mitochondrion

noun

mi·​to·​chon·​dri·​on ˌmī-tə-ˈkän-drē-ən How to pronounce mitochondrion (audio)
plural mitochondria ˌmī-tə-ˈkän-drē-ə How to pronounce mitochondrion (audio)
: any of various round or long cellular organelles of most eukaryotes that are found outside the nucleus, produce energy for the cell through cellular respiration, and are rich in fats, proteins, and enzymes see cell illustration
mitochondrial adjective

Examples of mitochondrion in a Sentence

Recent Examples on the Web That includes discovering that the mitochondrion had its own DNA. Elizabeth Cooney, STAT, 9 Aug. 2023 Burnetti would like to target mitochondria as well, but for a different reason. Byelizabeth Pennisi, science.org, 18 Apr. 2023 This is a cross section of a mitochondrion. Jennifer Barfield, Discover Magazine, 15 June 2018 When a mitochondrion is damaged, PINK1 and Parkin recruit a phagophore, which engulfs the organelle and begins the process of degrading it. Diana Kwon, Discover Magazine, 3 July 2021 The energy factory in animal cells like our own is the mitochondrion, a repository for channeling energy from glucose harvested from food into electrons. Zeeya Merali, Discover Magazine, 28 Dec. 2014 Quite literally, each mitochondrion becomes a battery, waiting to discharge. James Somers, The New Yorker, 25 Oct. 2022 The study propelled Chandel, then at the University of Chicago, and his colleagues to examine whether mitochondria could release other signals as well. Quanta Magazine, 18 Mar. 2019 For decades, researchers have known that mitochondria are derived from bacteria that became internal symbionts of archaeal cells, but details of how that happened have been sketchy. Quanta Magazine, 9 Apr. 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mitochondrion.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

borrowed from German (in plural Mitochondria), from Greek mítos "length of thread, cord used to separate warp threads" (of uncertain origin) + -o- -o- + chóndrion "granule," diminutive of chóndros "grain, groats" — more at chondro-

Note: Term introduced by the German microbiologist Carl Benda (1857-1932) in "Ueber die Spermatogenese der Vertebraten und höherer Evertebraten: II. Theil: Die Histiogenese der Spermien" [XVII. Sitzung am 29. Juli 1898], Archiv für Anatomie und Physiologie - Physiologische Abtheilung, Jahrgang 1898, p. 397: "Sie liegen innerhalb eines Theiles der Protoplasmafäden, bisweilen zu besonderen Körpern gehäuft, und sind wenigsten mit einem Theil der bereits bekannten Zellmikrosomen identisch, aber unterschieden von den Altmann'schen und Ehrlich'schen Granulationen. Ich möchte vorläufig vorschlagen, ihnen als Mitochondria eine besondere Stellung vorzubehalten, die ich in weiteren Arbeiten begründen werde." ("They lie within of a portion of the protoplasmic threads, sometimes aggregated to particular bodies, and are identical to at least part of the already known cell microsomes, but differ from Altmann's and Ehrlich's granulations. I would like to suggest tentatively reserving for them a special status as mitochondria, which I will substantiate in further work.")

First Known Use

1901, in the meaning defined above

Time Traveler
The first known use of mitochondrion was in 1901

Dictionary Entries Near mitochondrion

Cite this Entry

“Mitochondrion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mitochondrion. Accessed 19 Mar. 2024.

Kids Definition

mitochondrion

noun
mi·​to·​chon·​dri·​on ˌmīt-ə-ˈkän-drē-ən How to pronounce mitochondrion (audio)
plural mitochondria -drē-ə How to pronounce mitochondrion (audio)
: one of the round or long bodies found in the cytoplasm of cells outside the nucleus that are rich in fats, proteins, and enzymes and are important centers of metabolic processes which use oxygen and produce energy

Medical Definition

mitochondrion

noun
mi·​to·​chon·​dri·​on ˌmīt-ə-ˈkän-drē-ən How to pronounce mitochondrion (audio)
plural mitochondria -drē-ə How to pronounce mitochondrion (audio)
: any of various round or long cellular organelles of most eukaryotes that are found outside the nucleus, produce energy for the cell through cellular respiration, and are rich in fats, proteins, and enzymes

called also chondriosome

mitochondrial adjective
mitochondrially adverb

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