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Idea: ideography.

[French idéo-, from Greek idea, form, idea; see weid- in Indo-European roots.]
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.


combining form
of or indicating idea or ideas: ideology.
[from French idéo-, from Greek idea idea]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(aɪˈdi ə, aɪˈdiə)

1. any conception existing in the mind as a result of mental understanding, awareness, or activity.
2. a thought, conception, or notion.
3. an impression: Give me a general idea of what happened.
4. an opinion, view, or belief.
5. a plan of action; intention: with the idea of becoming an engineer.
6. a purpose or guiding principle: What was the idea of that?
7. a groundless supposition; fantasy.
8. Philos.
a. a concept developed by the mind.
b. a conception of what is desirable or ought to be; ideal.
c. (cap.) Platonism. Also called form. an archetype or pattern of which the individual objects in any natural class are imperfect copies and from which they derive their being.
9. a musical theme or figure.
10. Obs.
a. a likeness.
b. a mental image.
[1400–50; late Middle English idee < Middle French < Late Latin < Greek idéā form, kind, sort]
i•de′a•less, adj.
syn: idea, thought, conception, notion refer to a product of mental activity. idea refers to a mental representation that is the product of creative imagination: She had an excellent idea for the party. thought emphasizes the intellectual processes of reasoning, contemplating, reflecting, or recollecting: I welcomed his thoughts on the subject. conception suggests imaginative, creative, and somewhat intricate mental activity: The architect's conception of the building was a glass skyscraper. notion suggests a fleeting, vague, or imperfect thought: I had only a bare notion of how to proceed.
pron: See police.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.