GRANDMOTHER
grandma, grandmother, granny, grannie, gran, nan, nanna
(noun) the mother of your father or mother
Source: WordNet® 3.1
Etymology
Noun
grandmother (plural grandmothers)
A mother of someone's parent.
A female ancestor or progenitor.
Synonyms
• (mother of someone's parent): See grandmother
Antonyms
• (with regard to gender): grandfather
• (with regard to ancestry): granddaughter, grandson, grandchild
Hypernyms
• grandparent
Hyponyms
• maternal grandmother
• paternal grandmother
Source: Wiktionary
Grand"moth"er, n.
Definition: The mother of one's father or mother.
Source: Webster’s Unabridged Dictionary 1913 Edition