eti·​ol·​o·​gy ˌē-tē-ˈä-lə-jē How to pronounce etiology (audio)
plural etiologies
: cause, origin
specifically : the cause of a disease or abnormal condition
: a branch of knowledge concerned with causes
specifically : a branch of medical science concerned with the causes and origins of diseases

Example Sentences

The scarf had been purchased in one of those tiny, exquisitely organized stores that can seduce you into thinking it matters less what you wear than how you accessorize what you wear, and the scarf came in just the noncolor colors that I like: mustard and khaki and taupe, shades of dun, nothing too vivid, yet subtly enlivening. I have traced the etiology of this object the better to convey the irrational significance of its loss. Daphne Merkin, New York Times Magazine, 5 May 1991
In social terms, regardless of its etiology, memory loss may be a way of coping with harsh reality. Elizabeth W. Markson, Growing Old in America, (1985) 1987
I have Freud in my novel as a doctor someone has heard about somewhere, perhaps in Vindobo-na in Pannonia (Vienna in Austria to you), who thinks, though not in so many words, that neuroses have no somatic etiology. I call him Sameach, which is Hebrew for Freud. I also call him Efcharistimenos, which is Greek for Freud. Damn it, I couldn't spell it out more if I tried. Anthony Burgess, Times Literary Supplement, 2 Aug. 1985
Recent Examples on the Web However, there is plausible evidence for an infectious etiology, including observations that the disease is known to occur in outbreaks. Vincent Racaniello, Discover Magazine, 12 Jan. 2012 Upward of 300 pediatric hepatitis cases of unknown etiology or origin have been reported by more than two dozen countries, according to information drawn from the CDC, the European Center for Disease Prevention and Control, and the United Kingdom Health Security Agency (UKHSA). Helen Branswell, STAT, 9 May 2022 But the true etiology of Christina’s disease remains a medical enigma, one that continues to be explored in academic medicine. Rebecca Kreston, Discover Magazine, 30 Mar. 2016 All were treated with antibiotic drops and the infections quickly resolved, pointing to a bacterial etiology. Rebecca Kreston, Discover Magazine, 1 Mar. 2016 Research does not support popular accounts implicating physiological factors in menstrual chocolate craving etiology. Seriously Science, Discover Magazine, 26 July 2017 The World Health Organization (WHO) reported 169 cases of acute hepatitis of unknown etiology, ranging from 1 month to 16 years old, with approximately 10% requiring liver transplantation at least one death, according to an April 23 report. Shiv Sudhakar, Fox News, 28 Apr. 2022 Like most just-so stories, this appealing etiology has disintegrated under scrutiny. Richard Pallardy, Discover Magazine, 3 Nov. 2021 She was referred for evaluation of an allergic etiology before continuing her workup with a computed tomographic head scan. Seriously Science, Discover Magazine, 19 Aug. 2016 See More

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

Word History


Medieval Latin aetiologia statement of causes, from Greek aitiologia, from aitia cause

First Known Use

circa 1555, in the meaning defined at sense 1

Time Traveler
The first known use of etiology was circa 1555

Dictionary Entries Near etiology

Cite this Entry

“Etiology.” Dictionary, Merriam-Webster, Accessed 1 Jun. 2023.

Kids Definition


eti·​ol·​o·​gy ˌēt-ē-ˈäl-ə-jē How to pronounce etiology (audio)
: the cause or origin especially of a disease

Medical Definition


variants or chiefly British aetiology
plural etiologies
: the cause or causes of a disease or abnormal condition
some types of cancer have a viral etiology
a multiple etiology in which biological, psychological, and sociocultural factors all play a roleM. E. Jackson et al.
: a branch of medical science dealing with the causes and origin of diseases

More from Merriam-Webster on etiology

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