- The middle vascular tunic of the eye lying between the pigment epithelium and the sclera. SYN: choroidea [TA]. [G. choroeides, a false reading for chorioeides, like a membrane]
* * *cho·roid 'kō(ə)r-.ȯid, 'kȯ(ə)r- also cho·ri·oid 'kōr-ē-.ȯid, 'kȯr- n a vascular membrane containing large branched pigment cells that lies between the retina and the sclera of the eye called also choroid coatchoroid or cho·roi·dal kə-'rȯid-əl adj
* * *n.the layer of the eyeball between the retina and the sclera (see also Bruch's membrane). It contains blood vessels and a pigment that absorbs excess light and so prevents blurring of vision. See eye.• choroidal adj.
* * *cho·roid (korґoid) [chori- + -oid] 1. the thin, pigmented, vascular coat of the eyeball extending from the ora serrata to the optic nerve; it furnishes blood supply to the retina and conducts arteries and nerves to the anterior structures. Called also chorioid, choroidea [TA], and chorioidea. 2. resembling the chorion.
Choroid shown in relation to other coats and related structures of the eye.
Medical dictionary. 2011.