Family name Сиднеы (Sidney 
, Sydney , Сиднеы 
) , globally, is a common last name. The cognomen Сиднеы is characteristic of Saint Lucia, where it is quite a common surname, Jersey, and Cabo Verde (explore the name in all countries). In absolute terms, it most frequently occurs in the United States, Nigeria, and Australia. More prevalently, Сиднеы is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sydney, Sidney | South Africa, Zambia, United States, Brazil, Democratic Republic of the Congo |
| Сиднеы | Russia |