The Collaborative International Dictionary of English v.0.48:

Populous \Pop"u*lous\, a. [L. populosus, fr. populus people: cf.
   F. populeux.]
   1. Abounding in people; full of inhabitants; containing many
      inhabitants in proportion to the extent of the country.
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            Heaven, yet populous, retains
            Number sufficient to possess her realms. --Milton.
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   2. Popular; famous. [Obs.] --J. Webster.
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   3. Common; vulgar. [Obs.] --Arden of Feversham.
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   4. Numerous; in large number. [Obs.] "The dust . . . raised
      by your populous troops." --Shak.
      [1913 Webster] -- Pop"u*lous*ly, adv. --
      Pop"u*lous*ness, n.
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