You searched for: “cosmozoans
cosmozoan (s) (noun), cosmozoans (pl)
An imaginary creature that supposedly came to the Earth from an unknown region: It is hypothetically said that cosmozoans presumably came to earth and seeded life, for example UFOs, microbe-bearing comets, or meteoroids from other star systems, known as "panspermia".

The hypothesis goes on to say that cosmozoans, in the form of cosmic germs, came to the earth from some outer-space sources.