kneecap

American  

[nee-kap] / ˈniˌkæp /

noun

1. the patella.

2. a protective covering, usually knitted, for the knee.

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verb (used with object)

kneecapped, kneecapping

1. to cripple (a person) by shooting in the knee.

   Terrorists were kneecapping prospective jurors.

kneecap British  

/ ˈniːˌkæp /

noun

1. anatomy a nontechnical name for patella

2. another word for poleyn

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verb

1. (esp of certain terrorist groups) to shoot (a person) in the kneecap, esp as an act of retaliation

kneecap Scientific  

/ nē′kăp′ /

1. See patella

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Other Word Forms

• kneecapper
  noun

Etymology

Origin of kneecap

First recorded in 1650–60; knee + cap ¹

Explanation

Your kneecap is the bony plate that covers the joint in the middle of your leg, between your thigh and shin. Whales don't have kneecaps, but it might surprise you to know that mice and birds do. The kneecap is just what it sounds like, a protective cap for your vulnerable knee. While the official anatomical term is patella, it's far more common to call this body part a kneecap. When babies are small, their kneecaps are made of soft cartilage, but by the time they're about three they harden into strong bone. If you're a fan of Mafia movies, you might also recognize the verb kneecap, "to shoot someone in the knee."

Example Sentences

Late Friday, an Iranian official detailed Khamenei’s injuries for the first time, saying his kneecap and back had been wounded in the strike that killed his father.

From The Wall Street Journal • May 10, 2026

Few if any government spokespeople have done more to kneecap their own agency in court than McLaughlin.

From Slate • Feb. 18, 2026

Hill suffered torn ligaments and a dislocated kneecap in a game against the New York Jets last year, ending his season.

From Barron's • Feb. 17, 2026

Now, Mr Finger says, Mr Musk is trying to kneecap his most formidable competitor.

From BBC • Feb. 16, 2025

The kneecap is exposed, and the socket is cut away so I can flex, but it does pinch a little behind the knee.

From "The Running Dream" by Wendelin Van Draanen