Cognomen 贞竹 (贞竹 
) , across the world, is a very rare last name. The family name 贞竹 is habitual in Eastern Asia, particularly China, where it is an extremely rare surname. More frequently, 贞竹 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 贞竹 | China |