- grandsire⇄grandsire, noun, verb, -sired,-siring.
- grandsire⇄noun 1. (Archaic.) a grandfather.
2. (Archaic.) a forefather.
3. (Archaic.) an old man.
4. the sire of a sire of an animal.
5. a method of ringing the changes in bell ringing. - grandsire⇄v.t. to become the grandsire of.
Ex. I'm not unaware of the irony of a birth control proponent grandsiring a tribe such as this (Life).