n. A father's or mother's father; an ancestor immediately after the father or mother in lineal ascent. [ 1913 Webster ]
Grandfather longlegs. (Zool.)
a. Like a grandfather in age or manner; kind; benignant; indulgent. [ 1913 Webster ]
He was a grandfatherly sort of personage. Hawthorne. [ 1913 Webster ]
n. [ See Great, 10. ] The father of one's grandfather or grandmother. [ 1913 Webster ]