ocellus noun. [ǝ'sɛlǝs] Pl. -lli [-lʌɪ, -li:]. E19.
[Latin, dim. of oculus eye.]
1. Zoology. Each of the small simple, as distinct from the compound, eyes of insects, other arthropods, etc.; a simple or rudimentary eye or visual spot which is sensitive to light but does not form a focused image. Also occas., a facet of a compound eye, an ommatidium. E19.

2. A coloured spot surrounded by a ring or rings of different colour, as on some feathers, butterflies' wings, etc.; an eyelike spot. E19.

[TahlilGaran] English Dictionary ▲