Scorpii

Scorpii is the Latin genitive form of Scorpius, the zodiacal constellation commonly known as the Scorpion. In astronomical naming, Scorpii serves to indicate that a star or object belongs to the Scorpius constellation. The name appears in standard star designations such as Alpha Scorpii, Beta Scorpii, and Delta Scorpii, following the Bayer or Flamsteed conventions. The use of Scorpii helps distinguish stars by their constellation when a simple designation could refer to objects in different parts of the sky.

Prominent examples include Alpha Scorpii, more widely known as Antares, the brightest star in Scorpius and a red supergiant approximately 550 light-years away. Beta Scorpii, known as Acrab, is a multiple-star system. Delta Scorpii, called Dschubba, is a bright blue-white star that is a spectroscopic binary and has shown variability in brightness. Other Scorpii-designated stars include various Flamsteed and Bayer entries such as Mu Scorpii or Nu Scorpii, which serve to identify additional members of the constellation.

Scorpius lies in the southern sky near the center of the Milky Way region and contains several notable deep-sky objects, including open clusters M6 (the Butterfly Cluster) and M7 (Ptolemy's Cluster), as well as the globular cluster M4. The term Scorpii is thus a linguistic and navigational tool in astronomy rather than a separate celestial object.