in cosmology, vast cloud of gas that by contraction and condensation becomes a galaxy of stars. In evolutionary (big-bang) models of creation, protogalaxies appear early in the expansion phase of the universe; in the steady-state model they are slowly but continually forming from newly created matter.
PROTOGALAXY
Meaning of PROTOGALAXY in English
Britannica English vocabulary. Английский словарь Британика. 2012