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definitions

big daddy

noun (often initial capital letters) Informal.

a man regarded as the paternalistic head of a family.
the founder or a leading member of a company, organization, movement, etc.: the big daddy of soil conservation.
the federal government: to thank big daddy for the tax cut.
Chiefly Southern U.S. grandfather.

Origin of big daddy

First recorded in 1950–55
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Idioms and Phrases with big daddy

big daddy

1

An influential man, a big shot (see under big cheese), as in You'll have to get permission from big daddy. [Slang; mid-1900s]

2

A male sweetheart or friend, often a man considerably older than his female companion; a sugar daddy. [Slang; mid-1900s]

3

Grandfather. This usage originated in the South among African-Americans.

4

The largest or most important person or thing of its kind. For example, The United States has long been the big daddy of the Western Hemisphere, or The blue whale was the big daddy of the ocean. [Slang; 1960s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.