ˌæplɪˈkeɪʃən ˈdɪlɪdʒəns ˈɪndəstɹi a diligent effort it is a job requiring serious application conscientiousness in paying proper attention to a task; giving the degree of care required in a given situation persevering determination to perform a task his diligence won him quick promotions frugality and industry are still regarded as virtues