Sputnik Definition
Sputniksputniknoun 1. An artificial satellite that orbits the Earth, especially one of those launched by the former Soviet Union between 1957 and 1961.
Etymology: 1950s: Russian, meaning ‘travelling companion'. Sputnik 1 was the world's first artificial satellite, and Sputnik 2 carried the dog ‘Laika', the first living creature to go into space.