The Nobelist Nun in question is Teresa, a 6-letter word. Teresa was a Spanish Roman Catholic nun and missionary of the Congregation of the Missionary Sisters of the Immaculate Heart of Mary. She was awarded the Nobel Peace Prize in 1979 for her work in defense of human rights and social justice. She was also known for her charitable works, such as founding orphanages, hospitals, and homes for the elderly. Her legacy continues to inspire people around the world to this day.