[[A °verbal °marker is a jussive marker if it signals that the °clause is an °imperative sentence and the °subject is third person.]]
A jussive marker is thus a special kind of imperative marker.
"In many languages, non-addressee-oriented command forms – or non-canonical imperatives – stand apart from canonical imperatives in their expression and evolution. Alternative terms are available. The term ‘jussive’ can be used to cover commands to third person, and ‘hortative’ describes commands to first person." (Aikhenvald 2010: 396)