In Lacan's psychoanalytical theory, the term Jouissance denotates a kind of pleasure or enjoyment that is linked with sexual aspects. The concept of Jouissance is linked with Lacan's concept of desire. Lacan saw desire, as did Freud, as mental energy invested with an object and which seeks an outlet in order to achieve a low level of tension. Lacan's Jouissance, on the other hand, is linked to increased tension and the building up of desire. This is the way in which Lacan ties together enjoyment and desire and positions them both on sexual energies.
see: Lacanian Terminology