What does endodermis mean?
Endodermis is a specialized anatomical term, best known in botany for the innermost layer of a root's cortex. This thin boundary lies just outside the root's vascular cylinder, or stele, and its cells commonly bear Casparian strips that help regulate the movement of water and dissolved minerals into the vascular tissue. The term can also be found in older embryological descriptions, where it refers to the inner layer of an embryo's blastoderm, the region that gives rise to the endoderm; modern usage usually says simply endoderm for that germ layer. In a public-facing text, endodermis is worth keeping because it names a precise structural boundary rather than a general skin or covering. It is primarily a formal, scientific word used in plant anatomy and related biological discussion, and its unfamiliar ending should not be mistaken for an error. The related forms endodermal, ectoderm and mesoderm show the same Greek building blocks and make the spatial logic of the name easier to remember.
nounIn botany, the innermost layer of a plant root's cortex, where it borders the vascular cylinder or stele. In older embryological usage, the inner cell layer of the blastoderm that gives rise to the endoderm.
- The innermost layer of the cortex of a plant root, usually one cell thick and situated immediately outside the stele.
- The inner layer of an animal embryo's blastoderm, a chiefly historical sense for which the modern term endoderm is now usually preferred.
"Water crossing the endodermis is filtered before it reaches the xylem."
"Water crossing the endodermis is filtered before it reaches the xylem."
"Researchers stained the root endodermis to reveal the Casparian strips."
This plural is uncommon in ordinary prose but follows the traditional Latinized plural ending.
"The cross-sections showed clearly defined endodermides around the vascular tissue."
A root's endodermis is a microscopic gatekeeper around its vascular core, helping decide what passes inward.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does endodermis come from?
The word was formed in scientific Latin from the Greek elements endon, meaning “in” or “within,” and derma, meaning “skin.” Its name therefore describes an inner or inward layer. Related biological terms such as endoderm, ectoderm, mesoderm and epidermis reuse the same Greek root for “skin” with different spatial prefixes.
Related word forms
How endodermis is actually used
This is a formal, specialized term used chiefly in plant anatomy. The embryological sense is historical or archaic, with endoderm now preferred for the corresponding embryonic germ layer.
Easily confused with endodermis
The epidermis is a plant's outer protective covering, whereas the endodermis is the deeper root layer that separates the cortex from the vascular cylinder.