A spacecraft, or space vessel, was a natural term used to describe any sort of craft designed for simple orbital to more advanced space travel, in designs ranging from rockets and probes, to shuttles and spaceships.
Thadiun Okona once joked that "life is like loading twice your cargo weight onto your spacecraft. If it's canaries and you keep half of them flying all the time, you're alright." (TNG: "The Outrageous Okona")
The unauthorized use of a spacecraft was considered a crime by Starfleet. In 2375, Tom Paris served thirty days of solitary confinement in the brig of the USS Voyager for this offense, among others. (VOY: "Thirty Days")