The DICT Development Group

  Homologous \Ho*mol"o*gous\, a. [Gr. ? assenting, agreeing; ? the
     same + ? speech, discourse, proportion, ? to say, speak.]
     Having the same relative position, proportion, value, or
     structure. Especially:
     (a) (Geom.) Corresponding in relative position and
         proportion.
         [1913 Webster]
  
               In similar polygons, the corresponding sides,
               angles, diagonals, etc., are homologous. --Davies &
                                                    Peck (Math.
                                                    Dict.).
     (b) (Alg.) Having the same relative proportion or value, as
         the two antecedents or the two consequents of a
         proportion.
     (c) (Chem.) Characterized by homology; belonging to the same
         type or series; corresponding in composition and
         properties. See Homology, 3.
     (d) (Biol.) Being of the same typical structure; having like
         relations to a fundamental type to structure; as, those
         bones in the hand of man and the fore foot of a horse are
         homologous that correspond in their structural relations,
         that is, in their relations to the type structure of the
         fore limb in vertebrates.
         [1913 Webster]
  
     Homologous stimulus. (Physiol.) See under Stimulus.
        [1913 Webster]

  homologous
      adj 1: having the same evolutionary origin but not necessarily
             the same function; "the wing of a bat and the arm of a
             man are homologous" [ant: analogous, heterologic,
             heterological, heterologous]
      2: corresponding or similar in position or structure or function
         or characteristics; especially derived from an organism of
         the same species; "a homologous tissue graft" [ant:
         autologous, heterologous]

  22 Moby Thesaurus words for "homologous":
     analogous, answering, approximate, approximating, approximative,
     close, coequal, comparable, complemental, complementary,
     correspondent, corresponding, equipollent, equivalent, like, near,
     proximate, reciprocal, reciprocative, relatable, similar,
     tantamount