The Collaborative International Dictionary of English v.0.48:

Similar \Sim"i*lar\, a. [F. similaire, fr. L. similis like,
   similar. See Same, a., and cf. Simulate.]
   1. Exactly corresponding; resembling in all respects;
      precisely like.
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   2. Nearly corresponding; resembling in many respects;
      somewhat like; having a general likeness.
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   3. Homogenous; uniform. [R.] --Boyle.
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   Similar figures (Geom.), figures which differ from each
      other only in magnitude, being made up of the same number
      of like parts similarly situated.

   Similar rectilineal figures, such as have their several
      angles respectively equal, each to each, and their sides
      about the equal angles proportional.

   Similar solids, such as are contained by the same number of
      similar planes, similarly situated, and having like
      inclination to one another.
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