The Collaborative International Dictionary of English v.0.48:

Dogma \Dog"ma\ (d[o^]g"m[.a]), n.; pl. E. Dogmas
   (d[o^]g"m[.a]z), L. Dogmata (d[o^]g"m[.a]*t[.a]). [L.
   dogma, Gr. do`gma, pl. do`gmata, fr. dokei^n to think, seem,
   appear; akin to L. decet it is becoming. Cf. Decent.]
   1. That which is held as an opinion; a tenet; a doctrine.
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            The obscure and loose dogmas of early antiquity. --
                                                  Whewell.
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   2. A formally stated and authoritatively settled doctrine; a
      definite, established, and authoritative tenet.
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   3. A doctrinal notion asserted without regard to evidence or
      truth; an arbitrary dictum.

   Syn: tenet; opinion; proposition; doctrine.

   Usage: -- Dogma, Tenet. A tenet is that which is
          maintained as true with great firmness; as, the tenets
          of our holy religion. A dogma is that which is laid
          down with authority as indubitably true, especially a
          religious doctrine; as, the dogmas of the church. A
          tenet rests on its own intrinsic merits or demerits; a
          dogma rests on authority regarded as competent to
          decide and determine. Dogma has in our language
          acquired, to some extent, a repulsive sense, from its
          carrying with it the idea of undue authority or
          assumption. This is more fully the case with its
          derivatives dogmatical and dogmatism.
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