- the simple eyespot of certain invertebrates, as distinguished from the compound eye of an insect or the camera-type eye of vertebrates and cephalopods
- an eyelike spot, as on a peacock's feathers
Origin of ocellusL, diminutive of oculus, eye
- A simple eye, found in many invertebrates, consisting of a number of sensory cells and often a single lens.
- A marking that resembles an eye, as on the tail feathers of a male peacock; an eyespot.
Origin of ocellusLatin, diminutive of oculus, eye; see okw- in Indo-European roots.