Origin of cathexisModern Latin ; from Classical Greek k?thexis, a holding (; from katechein, to hold fast ; from kata-, down + echein, to hold from source Old English sige, victory): translated, translation of German besetzung, as used by Freud
Origin of cathexisGreek kathexis, holding, retention, from katekhein, to hold fast : kat-, kata-, intensive pref.; see cata– + ekhein, to hold; see segh- in Indo-European roots.
Ancient Greek κάθεξις (kathexis, holding, retention). Entered English language as a translation for the common everyday German word Besetzung, which in this context means "occupation" in the sense of a position or something being occupied or filled, and not a military occupation of a place or the filling of job positions (although it can also mean either of these in other contexts). In English translations, a Greek word was used to be more scientific.