It follows the same pattern you use for grandmother and great-grandmother. Joan Joan In a message dated 6/14/2012 11:58:01 A.M. Eastern Daylight Time, gale_gorman@me.com writes: Joan, Do you mean as in "Great Grand Aunt?" I can readily understand how a sister of my grandfather could be my "grand aunt" but then what does that make the sister of my great grandfather, my great grand aunt? Gale