The Oxford Latin Dictionary defines the expression as fitness, suitability, worthiness, visual impressiveness or distinction, dignity of style and gesture, rank, status, position, standing, esteem, importance, and honour.
[1] Authors who had used dignitas extensively in their writings and oratories include Cicero, Julius Caesar, Tacitus, and Livy.
Its importance within the hierarchical classes of Roman society meant many historical figures would kill, commit suicide (e.g., Mark Antony), or enter exile in order to preserve their dignitas.
Florus claimed that the stubbornness of Cato the Younger had driven Pompeius Magnus to prepare defences in order to build up his dignitas.
Cicero did not consider himself worthy of having dignitas alone because he felt that—by turning his back on the Roman public—he had neglected the duty of one whose life had normally exemplified the concept.