The word “sororal” shares a root with the word “sorority,” which might be more familiar. They both originate from the Latin word “soror,” which means “sister.” If a woman is particularly close to a platonic female friend, you might say that they have a sororal relationship. Sororities, first established in the United States in 1851, are communities for college-aged women. Members often refer to each other as “sisters,” and these sororal relationships established in young adulthood can continue throughout their lives.