L O S T   O B J E C T S
Alexis Oltmer (2014)

Sublimation :
is a mature type of defense mechanism where socially unacceptable impulses or idealizations are consciously transformed into socially acceptable actions or behavior, possibly resulting in a long-term conversion of the initial impulse

In the psychoanalytic theory of Jacques Lacan, objet petit a (object little-a) stands for the unattainable object of desire. It is sometimes called the object cause of desire. Lacan always insisted that the term should remain untranslated, "thus acquiring the status of an algebraic sign." (Écrits).
'The "a" in question stands for "autre" (other), the concept having been developed out of the Freudian "object" and Lacan's own exploitation of "otherness."