n. an arch; for example the arcus aortae (*aortic arch) or an arcus senilis or arcus juvenilis (see corneal arcus).
a white or greyish line in the periphery of the cornea, concentric with but separated from the edge by a clear zone. It begins above and below but may become a continuous ring. It consists of an infiltration of fatty material and is common in the elderly (arcus senilis). When it occurs in younger people (arcus juvenilis) it may indicate *hyperlipidaemia. It does not affect vision.... corneal arcus
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