Fovea

n. pit, small hole, dimple, depression (Biology)

The fovea, also known as the fovea centralis, is a part of the eye, located in the center of the macula region of the retina. The fovea is responsible for sharp central vision, which is necessary in humans for reading, watching television or movies, driving, and any activity where visual detail is of primary importance. The fovea is surrounded by the parafovea belt, and the perifovea outer region: the parafovea is the intermediate belt where the      ganglion cell layer is composed of more than five rows of cells; the perifovea is the outermost region where the ganglion cell layer contains two to four rows of cells, and is where visual acuity is below the optimum. This, in turn, is surrounded by a larger peripheral area that delivers information of low resolution.
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Fovea /fo·vea/ pl. fo´veae [L.] a small pit or depression. Often used alone to indicate the central fovea of the retina. [more]Fovea - Community and Resources

Noun
1. area consisting of a small depression in the retina containing cones and where vision is most acute
(synonym) fovea centralis
(hypernym) area, region
(part-holonym) retina

(n.)
A slight depression or pit; a fossa.