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1. A light-sensitive organelle of certain chiefly unicellular organisms, such as euglenas and some motile algae.
2. A simple visual organ of certain invertebrates, consisting of a cluster of photoreceptor cells and pigment cells.
3. A rounded eyelike marking, as on the wings of certain butterflies.
4. Any of several fungal diseases that affect grasses and are characterized by oval lesions.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
1. (Biology) a small area of light-sensitive pigment in some protozoans, algae, and other simple organisms
2. (Biology) an eyelike marking, as on the wings of certain butterflies
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
1. a light-sensitive group of cells or rudimentary visual structure of various algae and invertebrates.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
1. An area that is sensitive to light and functions somewhat like an eye, found in certain single-celled organisms as well as many invertebrate animals.
2. A round marking resembling an eye, as on the tail feather of a peacock.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.