Definition of choroid in English:

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Pronunciation: /ˈkɔːrɔɪd/
Pronunciation: /ˈkɒrɔɪd/


Resembling the chorion, particularly in containing many blood vessels.
Example sentences
  • As can be seen in the left hemisphere, the choroid plexus protrudes into the central part of the lateral ventricle, and the route of entry of the plexus is via the choroid fissure, between the fornix and the lamina affixa.
  • Medaka P is strongly expressed in the eyeball of embryos and adults, where melanin is produced in the choroid membrane and retinal pigment epithelium.
  • Thus the choroid plexuses of the lateral ventricles are in fact only lateral expansions of the tela choroidea of the 3rd ventricle, and they extend into the lateral ventricles by way of the choroid fissures.


(also choroid coat) The pigmented vascular layer of the eyeball between the retina and the sclera.
Example sentences
  • Underneath the retina is the choroid - a thin layer of blood vessels that supplies oxygen and nutrients to the retina.
  • These changes occur in the optic disc or the place from where the optic nerve exits the eye, the retina or the light sensitive layer and the layer behind the retina called the choroid.
  • Choroidal melanoma is a tumor of the eye that forms from pigmented cells of the choroid, a layer of vascular tissue in the back of the eye.



Example sentences
  • The final frame is a photograph from indocyanine green angiography, showing the detailed architecture of the choroidal vasculature
  • Fundal examination showed a large choroidal rupture of the left macula.
  • However, the neovascular, exudative form results in serous or hemorrhagic detachment of retinal pigment epithelium and choroidal neovascularization.


Mid 17th century: from Greek khoroeidēs (adjective), alteration of khorioeidēs, from khorion (see chorion).

For editors and proofreaders

Line breaks: chor|oid

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