The mother of one's father or mother; a grandmother.(noun)
An old woman.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "grandam" in a sentence
"Judith Merril was known as the grandam of science fiction and Phyllis as the mother of Canadian SF."
""When my father told me that my grandam" ( "grandam" has a good sound always, like a great oath) "had been murdered by de Morimont of Morimont Castle, I swore that the murder should not go unavenged."
"If they put Raul in the first movie other than being a baby or a youngster in the end with grandam then I will not see the movies to damaged the integrity of the books in such a way would be horrible!"