etiology
noun
eti·ol·o·gy ˌē-tē-ˈä-lə-jē 
plural etiologies
1
: cause, origin
specifically : the cause of a disease or abnormal condition
2
: 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
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 In the end, the etiology of eating disorders remains infuriatingly complex. Kate Willsky, Washington Post, 26 July 2022 People who are bipolar, like Jason, are more likely to develop PTSD after a traumatic event than the rest of the population, though the etiology and symptoms of the two illnesses are entirely different. New York Times, 5 July 2022 There have always been cases of hepatitis in children for which a cause cannot be found — such cases are labeled pediatric hepatitis of unknown etiology. Helen Branswell, STAT, 18 June 2022 Butler said this event could reveal that adenovirus 41 is responsible for a portion of pediatric hepatitis cases of unknown etiology, small numbers of which occur annually. Helen Branswell, STAT, 9 May 2022 Unlike with an infectious etiology, traveler’s constipation tends to arise from disruptions to your gut’s normal routine. Washington Post, 5 May 2022 Bray rejects this etiology of the disease, which implies that the anorexic, like so many Madame Bovaries before her, suffers simply from an inability to distinguish fact from fiction. Anna Shechtman, The New Yorker, 20 Dec. 2021 Tanzi, who specializes in Alzheimer's etiology and pathology research, said existing tests for Alzheimer’s risk involve positron emission tomography, or PET scans, as well as blood tests and genetic testing. Devon Link, USA TODAY, 29 Sep. 2021 At autopsy, researchers have reported the presence of viral protein in the actual heart muscle of deceased patients—so viral involvement is possible, though the true etiology may be multifactorial. Carolyn Barber, Fortune, 14 Dec. 2020 See More
Kate Willsky, Washington Post, 26 July 2022 People who are bipolar, like Jason, are more likely to develop PTSD after a traumatic event than the rest of the population, though the etiology and symptoms of the two illnesses are entirely different. New York Times, 5 July 2022 There have always been cases of hepatitis in children for which a cause cannot be found — such cases are labeled pediatric hepatitis of unknown etiology. Helen Branswell, STAT, 18 June 2022 Butler said this event could reveal that adenovirus 41 is responsible for a portion of pediatric hepatitis cases of unknown etiology, small numbers of which occur annually. Helen Branswell, STAT, 9 May 2022 Unlike with an infectious etiology, traveler’s constipation tends to arise from disruptions to your gut’s normal routine. Washington Post, 5 May 2022 Bray rejects this etiology of the disease, which implies that the anorexic, like so many Madame Bovaries before her, suffers simply from an inability to distinguish fact from fiction. Anna Shechtman, The New Yorker, 20 Dec. 2021 Tanzi, who specializes in Alzheimer's etiology and pathology research, said existing tests for Alzheimer’s risk involve positron emission tomography, or PET scans, as well as blood tests and genetic testing. Devon Link, USA TODAY, 29 Sep. 2021 At autopsy, researchers have reported the presence of viral protein in the actual heart muscle of deceased patients—so viral involvement is possible, though the true etiology may be multifactorial. Carolyn Barber, Fortune, 14 Dec. 2020 See More Word History
Etymology
Medieval Latin aetiologia statement of causes, from Greek aitiologia, from aitia cause
First Known Use
circa 1555, in the meaning defined at sense 1
Medical Definition
etiology
noun
eti·ol·o·gy
variants or chiefly British aetiology
ˌēt-ē-ˈäl-ə-jē
plural etiologies
1
: 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 role M. E. Jackson et al.
M. E. Jackson et al.2
: a branch of medical science dealing with the causes and origin of diseases