Real Object

"... the requaesitum which we have been seeking is simply that which the sign "stands for," or the idea of that which it is calculated to awaken. [---]
     This requaesitum I term the Object of the sign; - the immediate object, if it be the idea which the sign is built upon, the real object, if it be that real thing or circumstance upon which that idea is founded, as on bedrock." ('Pragmatism', EP 2:407, 1907)

"[O]ne must distinguish the Object as it is represented, which is called the Immediate Object, from the Object as it is in itself. The latter is purely active in the representation. That is, it remains in all respects exactly as it was before it was represented. It is true that the purpose of representing an Object is usually, if not always, to modify it in some respect. But by the Object Itself, or the Real Object, we mean the Object insofar as it is not modified by being represented." ([On Signs], MS 793:14, not dated)

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Abbreviations (CP, EP, etc.) and sources; see here