homologous Meaning, Definition & Usage

adjective having the same evolutionary origin but not necessarily the same function
- the wing of a bat and the arm of a man are homologous
adjective corresponding or similar in position or structure or function or characteristics; especially derived from an organism of the same species
- a homologous tissue graft

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.
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 thier relations to the type structure of the fore limb in vertebrates.