From Longman Dictionary of Contemporary Englishgrandparentgrand‧par‧ent /ˈɡrænˌpeərənt $ -ˌper-/ ●●● W3 noun [countable usually plural] SSFFAMILYone of the parents of your mother or father My grandparents live in Sussex.THESAURUSwords for grandparentsgrandfather/grandmotherShe looks just like grandmother. My grandfather was a farmer.grandpa informal grandfatherMy grandpa died when I was a baby.Ask Grandpa if he'll buy us an ice cream.grandma informal grandmotherI was at my grandma's house yesterday.grandad informal (also granddad American English) grandfatherGrandad collects me from school on Fridays.granny informal grandmotherGranny, can I come with you?nan/nanna British English informal grandmother – used especially by childrenShe's staying at her nan's.You can have a cuddle on the sofa with Nanna.
Examples from the Corpus
grandparent• Every human being has two parents, four grandparents, eight great-grandparents, sixteen great-great-grandparents, and so on.• I missed my grandparents desperately and longed for Pam.• My grandparents live in Oregon.• The role of grandparents is to give time and unconditional love.• This can be an aunt or grandparent or some other family member.• Across Route 22, in Union, my other grandparents sat choked in tinsel.• Our grandparents, then, Roman and Fenya Lubetkin.• My five-year-old godson's grandparents brought him a small, framed drawing for his christening present. 