adjective

homologous

hoh-MAH-luh-gus/həʊˈmɑːləɡəs/

Matching in underlying structure, origin, or relationship.

The bat's wing and whale's flipper contain homologous bones arranged in a shared pattern.

A side-by-side anatomical comparison of a bat wing and a whale flipper, with translucent outer contours exposing the corresponding forelimb bones.

Etymology

homoGreeksame

+logGreekrelation, reasoning

+ousEnglishhaving the nature of

“Same” plus “relation” gave a Greek adjective meaning “agreeing.” That idea of agreement underlies corresponding structures or positions, including similarities attributed to shared ancestry.

In context

Wendy Riggs5:03

Labia majora, two flaps. Guess what, if you have a Y chromosome, your labia major zips up. What? It does. It zips up closed and forms the scrotum. These are homologous structures.

Reproduction 8- Homologous structures

More examples

Homologous chromosomes carry the same genes but may have different versions.
Cactus spines are homologous to the leaves of other plants.
Homologous sides of similar triangles have proportional lengths.

Forms

homologous

homology noun — Correspondence based on shared structure or origin.

Similar words

analogous: Similar in function, but not necessarily in evolutionary origin.
corresponding: Matching in position or role, without necessarily sharing ancestry.