The Collaborative International Dictionary of English v.0.48:

Atlantean \At`lan*te"an\, a. [L. Atlant?us.]
   1. Of or pertaining to the isle Atlantis, which the ancients
      allege was sunk, and overwhelmed by the ocean.
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   2. Pertaining to, or resembling, Atlas; strong.
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            With Atlantean shoulders, fit to bear
            The weight of mightiest monarchies.   --Milton.
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