The definition of an idea is a thought, belief, opinion or plan.(noun)
An example of idea is a chef coming up with a new menu item.
See idea in Webster's New World College Dictionary
Origin: L < Gr, form or appearance of a thing as opposed to its reality < IE *widswo- < base *weid-, to see, know > L videre, to see, Gr idein, to see, OE witan, to know
See idea in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Latin
Origin: , from Greek; see weid- in Indo-European roots.
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