granddaddy
Concise Oxford English Dictionary © 2008 Oxford University Press:
grandaddy /ˈɡrandadi/ (also granddaddy)
▶noun (pl. grandaddies)
- 1 N. Amer. informal one's grandfather.
- 2 the largest or most notable example of a particular thing: the grandaddy of all headaches.
'granddaddy' also found in these Oxford entries:

