mitochondrion

noun

mi·​to·​chon·​dri·​on ˌmī-tə-ˈkän-drē-ən 

plural mitochondria ˌmī-tə-ˈkän-drē-ə 

: 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

ˌmī-tə-ˈkän-drē-əl 

adjective

Examples of mitochondrion in a Sentence

Recent Examples on the Web

These are the mitochondrion, where a former bacteria now handles the task of converting chemical energy into useful forms, and the chloroplast, where photosynthesis happens. —John Timmer, Ars Technica, 11 Apr. 2024

Similar systems are used by mitochondria and chloroplasts. —John Timmer, Ars Technica, 11 Apr. 2024

The mitochondrion is a pretty little thing under the microscope, a neat lozenge containing a labyrinth of membranes. —Quanta Magazine, 6 Mar. 2024

That includes discovering that the mitochondrion had its own DNA. —Elizabeth Cooney, STAT, 9 Aug. 2023

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

Kids Definition

mitochondrion

noun

mi·​to·​chon·​dri·​on ˌmīt-ə-ˈkän-drē-ən 

plural mitochondria -drē-ə 

: 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 

plural mitochondria -drē-ə 

: 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

-drē-əl 

adjective

mitochondrially

-ē 

adverb