From Longman Dictionary of Contemporary Englishpaternal grandmother/uncle etcpaternal grandmother/uncle etcFAMILYyour father’s mother, brother etc → paternal
Examples from the Corpus
paternal grandmother/uncle etc• In 1989 T. moved to live with her paternal grandmother and a year later she went to live with her boyfriend.• C.'s paternal grandmother applied for residence and contact.• The boy's father and paternal grandmother applied, interalia, for an order for the boy to reside with the grandmother.• The boy's paternal grandmother had unsuccessfully applied for a residence order.• At the home of his paternal uncle he was very much at home.• The infant girl was immediately named Margarett Williams Sargent for her paternal grandmother, who was eighty-three and ailing. 