What does zygomorphic mean?
Zygomorphic is a technical adjective meaning bilaterally symmetrical: a body or structure can be divided by one plane into corresponding mirror-image halves. In zoology and comparative anatomy, it describes an organism's single-plane symmetry and is often used when comparing body plans. The word appears most often in scientific descriptions rather than ordinary speech, so it should not be treated as a general label for any kind of symmetry. A zygomorphic form differs from a radially symmetrical one because the former has a single dividing plane, while the latter may be divided equally in several directions. The expression “zygomorphic symmetry” is standard technical phrasing. Knowing the word makes it possible to describe bilateral body plans precisely without relying on a longer explanatory phrase.
adjectiveBilaterally symmetrical, especially describing an organism or body structure that can be divided by a single plane into corresponding mirror-image halves.
- Having bilateral symmetry, with a body or structure that can be divided into mirror-image halves by a single plane.
"The fish had a zygomorphic body, with its fins arranged as near-perfect mirror images on either side."
"The fish had a zygomorphic body, with its fins arranged as near-perfect mirror images on either side."
"Taxonomists used the organism's zygomorphic symmetry as one of its defining anatomical traits."
A zygomorphic body has one principal mirror plane: split it through the middle, and the two halves correspond.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of zygomorphic
Zygomorphic combines the combining form zyg-, ultimately from Greek zygōn, meaning “yoke,” with morphē, meaning “form,” reflected in the suffix -morphic. In zoological usage, the compound developed as a description of a body exhibiting bilateral symmetry. Related words such as zygote, zygomatic, and zygodactyl share the Greek yoke-forming root, while isomorphic derives independently from Greek morphē and refers more broadly to similarity of form.
Related word forms
How zygomorphic is actually used
A formal, chiefly technical term used in zoology, comparative anatomy, taxonomy, and biological design. It describes single-plane bilateral symmetry and does not normally apply to radial or spherical symmetry.
Easily confused with zygomorphic
Isomorphic means similar or identical in form, whereas zygomorphic more specifically means bilaterally symmetrical along a single plane.