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Surname Sei (Sei
, سي
, セイ
, along with others...) , in all the world, is a common cognomen. The cognomen Sei is habitual in South Korea, where it is quite a common surname, Malaysia, where it is quite a rare surname, and Japan. Measured by absolute frequency, it is commonest in South Korea, Japan, and India. Also, Sei is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sei | India, Ghana, Malaysia, Japan, Myanmar |
| سي | Morocco, Algeria, Syria, Egypt, Sudan |
| セイ | Japan |
| Сей | Ukraine, Kazakhstan, Belarus, Russia, Kyrgyzstan |
| Сеи | Russia |
| 왕 | South Korea |