Definition of "granddaddy" []

• Informal A grandfather. (noun)
• Informal One that is the first, oldest, or most respected of its kind: the granddaddy of modern computers. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In 1964, we passed the Civil Rights Act, our main granddaddy of civil rights legislation."
• "Well, it's a program now referred to as the granddaddy of all reality television shows."
• "My granddaddy was a director of the meat plant and after World War II he was sent to rebuild the Soviet economy in various parts of former Soviet Union."