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Meaning of HOMOLOGY

Pronunciation:  hu'mâlujee

WordNet Dictionary
[n]  the quality of being similar or corresponding in position or value or structure or function

HOMOLOGY is a 8 letter word that starts with H.


 See Also: similarity



Webster's 1913 Dictionary
\Ho*mol"o*gy\, n. [Gr. ? agreement. See {Homologous}.]
1. The quality of being homologous; correspondence; relation;
   as, the homologyof similar polygons.

2. (Biol.) Correspondence or relation in type of structure in
   contradistinction to similarity of function; as, the
   relation in structure between the leg and arm of a man; or
   that between the arm of a man, the fore leg of a horse,
   the wing of a bird, and the fin of a fish, all these
   organs being modifications of one type of structure.

Note: Homology indicates genetic relationship, and according
      to Haeckel special homology should be defined in terms
      of identity of embryonic origin. See {Homotypy}, and

3. (Chem.) The correspondence or resemblance of substances
   belonging to the same type or series; a similarity of
   composition varying by a small, regular difference, and
   usually attended by a regular variation in physical
   properties; as, there is an homology between methane,
   {CH4}, ethane, {C2H6}, propane, {C3H8}, etc., all members
   of the paraffin series. In an extended sense, the term is
   applied to the relation between chemical elements of the
   same group; as, chlorine, bromine, and iodine are said to
   be in homology with each other. Cf. {Heterology}.

{General homology} (Biol.), the higher relation which a
   series of parts, or a single part, bears to the
   fundamental or general type on which the group is
   constituted. --Owen.

{Serial homology} (Biol.), representative or repetitive
   relation in the segments of the same organism, -- as in
   the lobster, where the parts follow each other in a
   straight line or series. --Owen. See {Homotypy}.

{Special homology} (Biol.), the correspondence of a part or
   organ with those of a different animal, as determined by
   relative position and connection. --Owen.

Biology Dictionary
 Definition: Two anatomical structures or behavioral traits within different organisms which originated from a structure or trait of their common ancestral organism. The structures or traits in their current forms may not necessarily perform the same functions in each organism, nor perform the functions it did in the common ancestor. They may even have become completely unused and therefore vestigial. Compare analogy.
  1. Similarity in DNA or protein sequences between individuals of the same species or among different species.
  2. a similarity due to inheritance from a common ancestor.
Thesaurus Terms
 Related Terms: accord, addition, adjunct, affairs, affiliation, affinity, alliance, approximation, assemblage, association, bond, closeness, combination, connectedness, connection, contiguity, contrariety, dealings, deduction, disjunction, filiation, intercourse, intimacy, junction, liaison, link, linkage, linking, mutual attraction, nearness, propinquity, proximity, rapport, relatedness, relation, relations, relationship, similarity, sympathy, tie, tie-in, union