eyespot

Noun

eyespot (countable and uncountable, plural eyespots)

1. (countable) Any of various primitive light-sensitive organs or regions in many diverse organisms.
   • The eyespot is a complex sandwich of membranes with rows of granules that contain around 200 different proteins, including the same rhodopsins found in the retina of our own eye.2011, Terence Allen, Graham Cowling, The Cell: A Very Short Introduction, Oxford, page 12
2. (countable) An eye-like marking on the tail of a peacock or the wing of a butterfly.

   Synonyms:

   ocellus

3. (countable) A coloured spot in a motile gamete or spore, which is sensitive to light.
4. Any of a group of fungal infections of grasses that are characterized by oval spots; strawbreaker.