noun /ʌɪˈdɪə,aɪˈdiə/
a) An abstract archetype of a given thing, compared to which real-life examples are seen as imperfect approximations; pure essence, as opposed to actual examples.
The remembrance whereof (which yet I beare deepely imprinted in my minde) representing me her visage and Idea so lively and so naturally, doth in some sort reconcile me unto her.
b) An image of an object that is formed in the mind or recalled by the memory.
The mere idea of you is enough to excite me.
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