nostra culpa exclamation 1noun 1forms 1 exclamation1 •Our fault, due to our error; we are to blame.The exponents of guilt routinely exempt themselves from their accusations; they do not speak of mea culpa but of nostra culpa, or rather vestra culpa. — 1984 noun1 •An instance of nostra culpa; an apology on behalf of a group. formsnostra culpas
