'Grandaunt' definitions:

Definition of 'grandaunt'

From: WordNet
noun
An aunt of your father or mother [syn: great-aunt, grandaunt]

Definition of 'Grandaunt'

From: GCIDE
  • Grandaunt \Grand"aunt"\, n. [Cf. F. grand'tante.] The aunt of one's father or mother. [1913 Webster]