The Collaborative International Dictionary of English v.0.48:

Atheous \A"the*ous\, a. [Gr. ? without God. See Atheist.]
   1. Atheistic; impious. [Obs.] --Milton.
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   2. Without God, neither accepting nor denying him.
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            I should say science was atheous, and therefore
            could not be atheistic.               --Bp. of
                                                  Carlisle.
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