Definition of protogalaxy in English:

protogalaxy

noun

Astronomy
  • A vast mass of gas from which a galaxy is thought to develop.

    • ‘Those that are still around us bear the imprint of the chemical composition of the protogalaxy in their atmospheres, like living fossils of a bygone era in the history of the Earth.’
    • ‘The protogalaxy probably has since coalesced into a giant elliptical galaxy, he says.’
    • ‘According to current models, that's not enough time to allow for the formation of either the quasars that illuminate the atomic gas or the protogalaxies that harbor the first stars.’

Pronunciation

protogalaxy

/ˌprōdōˈɡaləksē/