An American orbiting space laboratory launched in 1973, used for experiments in zero gravity and for astrophysical studies until 1974.
Definition of Skylab in US English:
Skylab
proper nounˈskīˌlab
A US orbiting space laboratory. Its three manned missions, all launched in 1973, were used for experiments in zero gravity and for astrophysical studies. Abandoned in 1974, it re-entered the earth's atmosphere in 1979, scattering debris in Australia and the Indian Ocean.