Subject of the Enunciated
The subject of enunciation is the "I" who speaks, the individual doing the speaking. The subject of the enunciated is the "I" of the sentence. "I" is not identical to itself - it is split between the individual "I" (the subject of enunciation) and the grammatical "I" (the subject of the enunciated).
It does not account for me in my full specificity; it is, rather, a general term I share with everyone else. In order to do so, my empirical reality must be annihilated or, as Lacan avers, "the symbol manifests itself first of all as the murder of the thing". The subject can only enter language by negating the Real, murdering or substituting the blood-and-sinew reality of self for the concept of self expressed in words.