What is the name of Ripley's cat in "Alien"?

The name of Ripley’s cat in “Alien” is Jonesy. The ginger cat is formally called Jones, but characters and fans commonly refer to him by the nickname Jonesy.

Jones is the ship’s cat aboard the commercial spacecraft Nostromo in Ridley Scott’s 1979 science-fiction horror film. His small size allows him to move through the ship unnoticed, and he becomes an important source of tension as the crew searches for the escaped Xenomorph.

Jonesy survives the events that kill most of the Nostromo crew. At one point, the crew’s motion tracker detects him instead of the Alien, sending Brett into the ship’s air shafts, where the creature attacks him. Ripley later rescues Jones and escapes with him aboard the shuttle Narcissus.

The cat’s official name can cause a minor quiz dispute: reference sources often list him as Jones, while the widely recognized character name is Jonesy. “Jonesy” is therefore the fair, canonical answer for a question phrased as Ripley’s cat’s name. Four cats reportedly portrayed the character during filming.