[ho.mol.o.gy] n, pl -gies (ca. 1656) 1: a similarity often attributable to common origin
2. a: likeness in structure between parts of different organisms due to evolutionary differentiation from the same or a corresponding part of a remote ancestor--compare analogy b: correspondence in structure between different parts of the same individual
3: similarity of nucleotide or amino-acid sequence in nucleic acids, peptides, or proteins
4: a branch of the theory of topology concerned with partitioning space into geometric components (as points, lines, and triangles) and with the study of the number and interrelationships of these components esp. by the use of group theory--called also homology theory--compare cohomology