CYG or Cyg or variant, may refer to:
Cygnus /ˈsɪɡnəs/ is a northern constellation lying on the plane of the Milky Way, deriving its name from the Latinized Greek word for swan.
Cygwin (/ˈsɪɡwɪn/ SIG-win) is a Unix-like environment and command-line interface for Microsoft Windows.
The Cygnus spacecraft is an American automated cargo spacecraft developed by Orbital ATK as part of NASA's Commercial Orbital Transportation Services (COTS) developmental program.
Cygnus X-1 (abbreviated Cyg X-1) is a galactic X-ray source in the constellation Cygnus, and the first such source widely accepted to be a black hole.
Cygnus CRS Orb-3, also known as Orbital Sciences CRS Flight 3 or Orbital 3, was an attempted flight of Cygnus, an automated cargo spacecraft developed by United States-based company Orbital Sciences, on 28 October 2014. This flight, which would have been its fourth to the International Space Station and the fifth of an Antares launch vehicle, resulted in the Antares rocket exploding seconds after liftoff.
The Cygnus Loop (radio source W78, or Sharpless 103) is a large supernova remnant (SNR) in the constellation Cygnus, an emission nebula measuring nearly 3° across.
Cygnus CRS OA-6, also known as Orbital Sciences CRS Flight 6, is the sixth flight of the Orbital ATK unmanned resupply spacecraft Cygnus and its fifth flight to the International Space Station under the Commercial Resupply Services contract with NASA.
Cygnus Orb-D1, also known as Cygnus 1 and Orbital Sciences COTS Demo Flight, was the first flight of the Cygnus unmanned resupply spacecraft developed by Orbital Sciences Corporation.
Cygnus CRS Orb-1, also known as Orbital-1, was the second flight of the Orbital Sciences Cygnus unmanned resupply spacecraft, its second flight to the International Space Station and the third launch of the company's Antares launch vehicle.