kidneys

IPA/ˈkɪd.ni/
KK[kˈɪdniz]IPA/ˈkɪd.ni/

kidneys — noun

  • kidneyssingular
  • kidneysesplural

1. two bean-shaped organs inside your body, one on each side of your spine, that cl

1.nounB1
Definition

two bean-shaped organs inside your body, one on each side of your spine, that clean your blood by removing waste and turning it into urine.

Example

Mei drinks a lot of water every day to keep her kidneys healthy.

collocation: keep kidneys healthy

The doctor told Kofi that his kidneys were working well after the blood test.

kidneys + verb (working well)

Common collocations
  • kidney function
  • kidney disease
  • kidney failure
  • kidney transplant
  • kidney stone
  • donate a kidney
  • healthy kidneys

Grammar Patterns

kidneys + verb (filter / produce / remove)

Usage Note

Usually used in the plural (kidneys) because they come as a pair. The singular (kidney) is used when referring to just one organ, e.g., 'He donated a kidney to his brother.'

Common Mistakes

My kidneys are producing too much water.
My kidneys are producing too much urine.
Kidneys produce urine, not plain water.
My kidney was hurting, but the doctor said it was fine. She said I should drink more water.
My kidneys were hurting, but the doctor said they were fine. She said I should drink more water.
The plural 'kidneys' is normally used because humans have two kidneys. Use the singular only when talking about one specific kidney.

2. the kidneys of an animal such as a cow, pig, or lamb, prepared as meat and cooke

2.nounB2
Definition

the kidneys of an animal such as a cow, pig, or lamb, prepared as meat and cooked for eating.

Example

Takeshi ordered grilled kidneys with onions and a side of rice for dinner.

collocation: grilled kidneys + with onions

The traditional British recipe cooks lamb kidneys slowly in a rich gravy.

variety: British dish; collocation: lamb kidneys

Common collocations
  • lamb kidneys
  • pig kidneys
  • grilled kidneys
  • kidney stew
  • kidney pie
  • kidney in gravy
Synonyms
  • offal

    broader term that includes kidneys, liver, heart, and other organ meats

  • organ meat

    more general term for edible animal organs

Grammar Patterns

cook/eat/have + kidneys

kidneys + served/cooked/grilled

Usage Note

Common in British and Irish cooking but less popular in American cuisine. Often paired with strong flavours like mustard, herbs, or onion to balance the distinctive taste. In Taiwan, pig kidneys (腰子) are common in soups and stir-fries.

Common Mistakes

I ate kidney for breakfast — the doctor removed it yesterday.
I ate kidneys for breakfast
my grandmother cooked them with onions.' — The food sense never refers to a human organ being eaten. Use 'lamb kidneys' or 'pig kidneys' to clarify it is meat.
Kidney is a type of white meat like chicken.
Kidney is a type of organ meat, also called offal.
Kidneys are not muscle meat; they belong to the offal category.

Word family

Synonym discussion

Sense: noun/1

Kidneys, liver, heart, lungs, and bladder are all internal organs, but they perform very different jobs. The kidneys are the body's filters — they clean waste from the blood and produce urine. The liver also filters blood but handles toxins, produces bile, and stores energy. The heart pumps blood around the body. The lungs exchange oxygen and carbon dioxide when you breathe. The bladder stores urine until it leaves the body. A common mix-up among learners is confusing kidneys with the liver because both are 'filters,' but the liver does many more jobs. For example: 'He needs a kidney transplant because his kidneys failed, but his liver is still healthy.'

kidney ↗liver ↗heart ↗lung ↗bladder ↗

Common collocations

Nouns

Phrases

  • kidney function test
  • chronic kidney disease
  • kidney transplant surgery
  • polycystic kidney disease

Prepositions

  • in the kidneys
  • of the kidneys
  • with kidneys

Etymology

Old EnglishOld NorseMiddle EnglishEnglish

The word 'kidney' comes from Middle English 'kidenei,' whose origin is not completely certain. The first part 'kid-' may come from an old English word 'cwiþ' meaning 'belly' or 'womb.' The second part '-ney' may be related to Old Norse 'nýra' (kidney) or to the word 'egg' (because of the organ's oval shape). Together, the word literally meant something like 'belly organ.'

First known use

14th century

14th century, in the meaning defined at sense 1a