ocellus

[oh-sel-uh s]

noun, plural o·cel·li [oh-sel-ahy] /oʊˈsɛl aɪ/.

a type of simple eye common to invertebrates, consisting of retinal cells, pigments, and nerve fibers.

an eyelike spot, as on a peacock feather.

Nearby words

Origin of ocellus

1810–20; < Latin: little eye, diminutive of oculus eye; see -elle

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ocellus

I will next describe the other extreme of the series, namely the first trace of an ocellus.
The Descent of Man and Selection in Relation to Sex|Charles Darwin
Ocellus: a simple eye, consisting of a single convex or bead-like lens, which conveys an image to a retina.
Explanation of Terms Used in Entomology|John. B. Smith
When the ocellus includes a lunular spot of a different colour.
An Introduction to Entomology: Vol. IV (of 4)|William Kirby
Occasionally specimens have a minute ocellus below the large one on the fore-wings.
New Zealand Moths and Butterflies|G. V. Hudson

Frontal lobes: in Psyllidae, two lobes or swellings more or less completely divided by a suture in which an ocellus is situated.
Explanation of Terms Used in Entomology|John. B. Smith

British Dictionary definitions for ocellus

ocellus

noun plural -li (-laɪ)

the simple eye of insects and some other invertebrates, consisting basically of light-sensitive cells

any eyelike marking in animals, such as the eyespot on the tail feather of a peacock

botany

an enlarged discoloured cell in a leaf
a swelling on the sporangium of certain fungi

Derived Formsocellar, adjectiveocellate (ˈɒsɪˌleɪt) or ocellated (ˈɒsɪˌleɪtɪd), adjectiveocellation, noun

Word Origin for ocellus

C19: via New Latin from Latin: small eye, from oculus eye

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for ocellus

ocellus

[ō-sĕl′əs]

Plural ocelli (ō-sĕl′ī′)

A small, simple eye or eyespot, found in many invertebrates.

A marking that resembles an eye, as on the wings of some butterflies.