kidney
Americannoun
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kidneys
plural
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Anatomy. either of a pair of bean-shaped organs in the back part of the abdominal cavity that form and excrete urine, regulate fluid and electrolyte balance, and act as endocrine glands.
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Zoology. a corresponding organ in other vertebrate animals or an organ of like function in invertebrates.
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the meat of an animal's kidney used as food.
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constitution or temperament.
He was a quiet child, of a different kidney from his boisterous brothers.
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kind, sort, or class.
He is only at ease with men of his own kidney.
noun
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either of two bean-shaped organs at the back of the abdominal cavity in man, one on each side of the spinal column. They maintain water and electrolyte balance and filter waste products from the blood, which are excreted as urine
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the corresponding organ in other animals
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the kidneys of certain animals used as food
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class, type, or disposition (esp in the phrases of the same or a different kidney )
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Either of a pair of organs that are located in the rear of the abdominal cavity in vertebrates. The kidneys regulate fluid balance in the body and filter out wastes from the blood in the form of urine. The functional unit of the kidney is the nephron. Wastes filtered from the blood by the nephrons drain into the ureters, muscular tubes that connect each kidney to the bladder.
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See also nephron
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of kidney
1275–1325; Middle English kidenei, kidenere (singular), kideneres, kideneren (plural); origin uncertain; perhaps a compound based either on nere (singular), neres (plural) kidney ( Old English *nēore; compare Old High German nioro, Old Norse nȳra ); or ei (singular), eiren (plural) egg 1, Old English ǣg (singular), ǣgru (plural) (by association with the organ's shape); for the first element compare dial. kid pod (akin to cod 2 )
Explanation
Most people are born with two kidneys, internal organs with the job of filtering waste and excreting urine. All vertebrates — animals with spines — have kidneys. Human kidneys are shaped like large beans, and this is where the "kidney bean," a common red-colored bean, gets its name. The organs called kidneys are vital to life, as they filter bad stuff from your blood, help your body get rid of waste, regulate your blood pressure, and even produce hormones. The word kidney is probably a compound of the Old English cwið, "womb," and ey, "egg," describing the organ's shape.
Vocabulary lists containing kidney
Human Anatomy and Physiology - Introductory
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Human Anatomy and Physiology - High School
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Human Anatomy and Physiology - Middle School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
The corresponding figures were 42% and 48% for liver cancer, 49% and 53% for bowel cancer, 29% and 33% for kidney cancer, and 36% and 34% for pancreatic cancer.
From Science Daily ● Oct. 14, 2026
Stanford University researchers trained an AI model, which from a single night’s sleep, can flag a person’s risk for roughly 130 diseases, including heart attack, stroke, kidney failure and dementia, years before diagnosis.
From MarketWatch ● Oct. 13, 2026
I had had a kidney transplant from Phillip Palmer, who’s the morning anchor at ABC7, and it was a really big story back in 2007.
From Los Angeles Times ● Oct. 1, 2026
When he got to the hospital in Nottinghamshire, Patrick said his mother was "totally unconscious", suffering continuous fits and going into kidney failure.
From BBC ● Oct. 1, 2026
Among the many symptoms associated with overexposure are blindness, insomnia, kidney failure, hearing loss, cancer, palsies, and convulsions.
From "A Short History of Nearly Everything" by Bill Bryson
Researchers suspect the genetic difference may influence how effectively the kidneys remove ImP from the blood, affecting how much of the compound remains in circulation.
From Science Daily ● Oct. 3, 2026
"I thought this lady needs one of my kidneys more than I need two of them," said Gary.
From BBC ● Sep. 16, 2026
Gary Summerfield saw the mum-of-four's post and, after learning he was a match, donated one of his kidneys via an operation in July.
From BBC ● Sep. 16, 2026
Our kidneys can handle a lot of fluid.
From The Wall Street Journal ● Aug. 27, 2026
His liver, kidneys, lungs, hands, feet, and head are becoming jammed with blood clots.
From "The Hot Zone" by Richard Preston
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