Nanna is a word typically used to refer to a grandmother or grandparent. However, there are many synonyms for this word, some of which are regional or even idiosyncratic. In the United States, some common alternatives to nanna include grandma, granny, grammy, and nan. Other countries may have their own variations on this term, such as Oma in Germany or Nonna in Italy. Additionally, some families may use unique or playful names for their grandparents, such as Mimi, Gigi, or Nanny. Ultimately, the word used to refer to a grandparent is a personal choice, and can reflect cultural traditions or family preferences.