Synonyms for Eyecup (same or very similar meaning)
WordNet sense 1 (a small vessel with a rim curved to fit the orbit of the eye; use to apply medicated or cleansing solution to the eyeball):
eyebathWordNet sense 2 ((embryology) a two-walled cuplike depression that develops into the pigmented and sensory layers of the retina):
optic cupFrom the ODE community, based on WordNetadd/edit