The definition of a mirage is an optical illusion, something that you believe you see but that isn't really there.
(noun)An example of a mirage is when you believe you see water or a ship in the desert when it isn't really there.
See mirage in Webster's New World College Dictionary
noun
Origin: Fr < (se) mirer, to be reflected < VL mirare, to look at, for L mirari: see miracle
See mirage in American Heritage Dictionary 4
noun
Origin:
Origin: French
Origin: , from mirer, to look at
Origin: , from Latin mīrārī, to wonder at
Origin: , from mīrus, wonderful; see smei- in Indo-European roots
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