(often caps.) Informal.
1. a man regarded as the paternalistic head of a family.
2. the founder or a leading member of a company, organization, movement, etc.: the big daddy of soil conservation.
3. the federal government: to thank big daddy for the tax cut.
4. Chiefly Southern U.S.grandfather.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.