call of duty—smth. that a person is required to do by one’s moral or social obligations:
- It was cruel of me to ask him to recount the events of the fateful day but it was the call of duty.
Cf.: (above and) beyond the call of duty—doing much more than should normally be expected of one (originally of heroic police officers, fire fighters, etc.):
- The deep level of care and compassion that was demonstrated to me was beyond the call of duty.
duty call—a visit undertaken as a duty or as part of one’s social obligations:
- They had accepted a dinner invitation over in Arlington—a duty call, as Andy termed it.