Definify.com
Webster 1913 Edition
Homology
1.
The quality of being homologous; correspondence; relation;
as, the
. homology
of similar polygons2.
(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.
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
, all members of the paraffin series. In an extended sense, the term is applied to the relation between chemical elements of the same group; homology
between methane, CH4
, ethane, C2H6
, propane, C3H8
, etc.as, chlorine, bromine, and iodine are said to be in
. Cf. homology
with each otherHeterology
. 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.