nos·​o·​co·​mi·​al ˌnä-sə-ˈkō-mē-əl How to pronounce nosocomial (audio)
: acquired or occurring in a hospital
nosocomial infection

Did you know?

Nosocomial is a word that usually occurs in formal medical contexts—specifically, in reference to hospital-acquired sickness. We hope you never encounter nosocomial as part of your own medical diagnosis, but if you do, you might want to remember that the term descends from nosocomium, the Late Latin word for "hospital." Nosocomium in turn traces to the Greek nosos, meaning "disease." That root has given English other words as well, including zoonosis ("a disease communicable from animals to humans under natural conditions") and nosology ("a classification or list of diseases" or "a branch of medical science that deals with classification of diseases").

Examples of nosocomial in a Sentence

Recent Examples on the Web And, hopping from one chaotic health care facility to the next provides opportunities for fragile patients to pick up and spread multi-drug resistant infections from bacteria that lurk in health care settings—aka nosocomial infections. Jennifer Ouellette, Ars Technica, 11 July 2023 High load of multi-drug resistant nosocomial neonatal pathogens carried by cockroaches in a neonatal intensive care unit at Tikur Anbessa specialized hospital, Addis Ababa, Ethiopia. Rebecca Kreston, Discover Magazine, 9 May 2012 The MedPAR data was also used to calculate the national nosocomial covid rate of 1.7%, with 6,629 of 394,939 covid patients diagnosed with the virus that was deemed not present on admission. Christina Jewett, CNN, 7 Nov. 2021

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

Word History


borrowed from New Latin nosocomiālis, from Late Latin nosocomium "hospital, infirmary" (borrowed from Late Greek nosokomeîon, derivative, with the suffix of place -eion, of Greek nosokoméō, nosokomeîn "to tend the sick," from nósos "disease" + -o- -o- + koméō, komeîn "to take care of, tend") + Latin -ālis -al entry 1; koméō probably iterative derivative from the base of kámnō, kámnein, aorist ékamon "to labor, take pains, be sick," going back to an Indo-European verbal base *ḱemh2- "take pains, tire," whence also Sanskrit áśamīt "(s/he) became quiet," śaśamé "(s/he) has taken pains," śā́myati "(s/he) becomes quiet, fatigues, ceases," Greek akámatos "not resting, untiring" — more at nosology

First Known Use

circa 1843, in the meaning defined above

Time Traveler
The first known use of nosocomial was circa 1843


Dictionary Entries Near nosocomial

Cite this Entry

“Nosocomial.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2024.

Medical Definition


nos·​o·​co·​mi·​al ˌnäs-ə-ˈkō-mē-əl How to pronounce nosocomial (audio)
: acquired or occurring in a hospital
nosocomial infection
nosocomially adverb
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!