The term "sinthome" was introduced by Jacques Lacan in his seminar Le sinthome (1975–76). According to Lacan, sinthome is the Latin way (1495 Rabelais, IV,63) of spelling the Greek origin of the French word symptôme, meaning symptom. The seminar is a continuing elaboration of his topology, extending the previous seminar's focus (RSI) on the Borromean Knot and an exploration of the writings of James Joyce. Lacan redefines the psychoanalytic symptom in terms of his topology of the subject.
In "Psychoanalysis and its Teachings" (Écrits) Lacan views the symptom as inscribed in a writing process, not as ciphered message which was the traditional notion. In his seminar "L'angoisse" (1962-63) he states that the symptom does not call for interpretation: in itself it is not a call to the Other but a pure jouissance addressed to no one. This is a shift from the linguistic definition of the symptom — as a signifier — to his assertion that "the symptom can only be defined as the way in which each subject enjoys (jouit) the unconscious in so far as the unconscious determines the subject." He goes from conceiving the symptom as a message which can be deciphered by reference to the unconscious structured like a language to seeing it as the trace of the particular modality of the subject's jouissance.
This shift from linguistics to topology constitutes the status of the sinthome as unanalyzable. The seminar extends the theory of the Borromean knot, which in RSI (Real, Symbolic, Imaginary) had been proposed as the structure of the subject, by adding the sinthome as the fourth ring to the triad already mentioned, tying together a knot which constantly threatens to come undone. Since meaning (sens) is already figured within the knot, at the intersection of the Symbolic and the Imaginary, it follows that the function of the sinthome — knotting together the Real, the Imaginary and the Symbolic — is beyond meaning.