Cognomen Cydney (Cydney 
, Сидни 
) , all over the world, is a very rare surname. The family name Cydney is characteristic of Nigeria, where it is an extremely rare surname, Mexico, and the United States. Much more prevalently, Cydney is the forename as well as the last name.
Cox, Barnes, Brooks, Parker, Palmer, Graham, Taylor, Thomas, Turner, Nelson, Harris, Walker, Wilson, Chapman, Collins, Jackson, Johnson, Mitchell, Anderson, Robinson, Williams, Henderson, Cooper, Carter, Miller, Morris, Lee, Fox, King, Ross, Gray, Hall, Hill, West, Moore, Smith, Richardson, Adams, Brown, Davis, Dixon, Green, James, Jones, Hayes, White, Young, Martin, Clark, and Washington