• synonyms


[oh-sel-uh s]
noun, plural o·cel·li [oh-sel-ahy] /oʊˈsɛl aɪ/.
  1. a type of simple eye common to invertebrates, consisting of retinal cells, pigments, and nerve fibers.
  2. an eyelike spot, as on a peacock feather.
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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. 2018

Examples from the Web for ocellus

Historical Examples of ocellus

  • Ocellus, Count of Nantes, and most of the inhabitants of Brittany, were buried in that city.

    Mediaeval Tales


  • The usual markings occur, but there is no eye-spot, or ocellus, on the primaries.

    The Butterfly Book

    William Jacob Holland

  • An ocellus with a smaller near it, called also Sesquiocellus.

  • The lower margin or base of the dark-blue centre of the ocellus is deeply indented on the line of the shaft.

  • The shading above the white mark on the summit of the ocellus is here a little too dark.

British Dictionary definitions for ocellus


noun plural -li (-laɪ)
  1. the simple eye of insects and some other invertebrates, consisting basically of light-sensitive cells
  2. any eyelike marking in animals, such as the eyespot on the tail feather of a peacock
  3. botany
    1. an enlarged discoloured cell in a leaf
    2. a swelling on the sporangium of certain fungi
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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

ocellus in Science


Plural ocelli (ō-sĕlī′)
  1. A small, simple eye or eyespot, found in many invertebrates.
  2. A marking that resembles an eye, as on the wings of some butterflies.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.