How to Write 髌 (bìn) — Meaning “patella / kneecap”

Imagine a guest (宾) arriving and accidentally bumping their knee on a table — the bone (骨) that hurts is the kneecap. Another way: think of "bin" as in "binoculars" — your two kneecaps look like a pair of binoculars when you kneel. This links the sound and the meaning to the patella.

Start with the left radical 骨: write the top part (⺼) first, then the middle 冎, and finally the bottom 月 — note the small hook at the bottom of 月. For the right side 宾, write the top 宀 with a dot, then the middle 弓, and finally the bottom 贝 — avoid making the 弓 too wide. A common mistake is forgetting the dot on top of 宀 or writing the 骨 radical too narrow.

髌 (bìn) specifically means kneecap, while 髀 (bì) refers to the thigh bone or hip (femur), and 髁 (kē) means the condyle (a rounded bone bump at a joint). Visually, 髌 has 宾 on the right, 髀 has 卑, and 髁 has 果. In usage, 髌 is limited to the patella, while 髀 appears in ancient texts for the upper leg.

髌 is almost exclusively used in medical and anatomical contexts, especially in terms like 髌骨 (kneecap) and 髌腱炎 (patellar tendonitis). You might see it in sports injury reports or orthopedic textbooks. It is not common in everyday conversation but is known by athletes and medical professionals.

Common words containing 髌 include: 髌骨 (bìn gǔ) — patella / kneecap; 髌韧带 (bìn rèn dài) — patellar ligament; 髌腱炎 (bìn jiàn yán) — patellar tendonitis.