patella

American  

[puh-tel-uh] / pəˈtɛl ə /

noun

plural

patellas, patellae

1. Anatomy. the flat, movable bone at the front of the knee; kneecap.

2. Biology. a panlike or cuplike formation.

3. Zoology. any limpet of the family Patellidae.

4. Archaeology. a small pan or shallow vessel.

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patella British  

/ pəˈtɛlə /

noun

1. Nontechnical name: kneecap.  anatomy a small flat triangular bone in front of and protecting the knee joint

2. biology a cuplike structure, such as the spore-producing body of certain ascomycetous fungi

3. archaeol a small pan

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patella Scientific  

/ pə-tĕl′ə /

plural

patellae

1. The small, flat, movable bone at the front of the knee in most mammals.

2. Also called kneecap

3. See more at skeleton

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Other Word Forms

• patellar adjective
• postpatellar adjective
• subpatellar adjective

Etymology

Origin of patella

1665–75; < Latin, diminutive of patina, patena pan, literally, something wide open. See paten, -elle

Explanation

The patella is the protective bone at the front of your knee. Next time you bang your leg on the edge of the coffee table, you can say, "Ow, my patella!" The patella is more commonly called a "kneecap." This bone resembles a triangle with rounded corners, perfectly shaped to protect your knee joint from injury. When you were born, your patella was just soft cartilage, but it hardened as you grew. Like humans, many other animals also have patellas, including mice, dogs — and even birds!

Example Sentences

But they are short of attacking midfielders - Maddison will take a long time to recover from his ACL injury, while Dejan Kulusevski is recovering from a long-term patella issue.

From BBC • Aug. 11, 2025

There was nothing unusual in their collision, but a coincidence of torsion and tension ruptured Roigard’s patella tendon.

From BBC • Oct. 30, 2024

Scoles, six months removed from two knee surgeries to correct a patella tendon that was peeling off her bone, was forced to withdraw from competition.

From Los Angeles Times • May 19, 2024

Seidel revealed Thursday on Instagram that she hurt her knee about a month ago and an MRI showed she had a fractured patella and partially torn patellar tendon.

From Seattle Times • Feb. 1, 2024

“Furthermore, each leg of mine has seven sections—the coxa, the trochanter, the femur, the patella, the tibia, the metatarsus, and the tarsus.”

From "Charlotte's Web" by E.B. White