1A prominent northern constellation (the Swan), said to represent a flying swan that was the form adopted by Zeus on one occasion. It contains the bright star Deneb.

1. 1.1as genitive Cygni /ˈsɪɡni/ Used with preceding letter or numeral to designate a star in the constellation Cygnus.
   与其前面的字母或数字连用以标记该星座中的星天鹅（星）座的
   the star Delta Cygni

   天鹅座δ星。