[proh-toh-gal-uhk-see, proh-toh-gal-]
noun, plural protogalaxies. Astronomy.
the large concentration of gas and dust from which a galaxy is formed.

1945–50; proto- + galaxy Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
protogalaxy (ˌprəʊtəʊˈɡæləksɪ)
n , pl -axies
a cloud of gas in the early stages of its evolution into a galaxy

Collins English Dictionary - Complete & Unabridged 10th Edition
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Encyclopedia Britannica


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

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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