'Grandpa' definitions:

Definition of 'grandpa'

(from WordNet)
noun
The father of your father or mother [syn: grandfather, gramps, granddad, grandad, granddaddy, grandpa]

Definition of 'Grandpa'

From: GCIDE
  • Grandpa \Grand"pa"\, Grandpapa \Grand"pa*pa"\, n. A grandfather. [1913 Webster]