" mother lode "

 [ "mother lode" ]

1: abundant source or supply

  * e.g.,  ... New York is the mother lode of neurotic writers. 

 [ "mother lode" ]

1: Originally meaning a main vein in mining, the spelling “motherload” is a mistake which is probably influenced by people thinking it means “the mother of all heavy loads.” A “lode” was originally a stream of water, but by analogy it became a vein of metal ore. A vein of mineral ore deposited between clearly demarcated layers of rock ahdictionary dot com Miners of precious metals live to find a 'lode' of gold, which they refer to as a “mother lode,” often spelled as two words, sometimes as one (neither is in the dictionary though). Definition paraphrased from Washington State University website

  * e.g.,  ... Son of a bitch, we struck the mother lode! in the 1976 classic film Network 

 [ "mother lode" ]

1: A very rich seam in a gold mine, a dream or a phantasm !

  * e.g.,  ... "his head full of dreams about the mother lode buried somewhere inside" (James Lee Burke, Swan Peak, 2008) 

 [ "Mother lode" ]

1: Clusters of peanuts, dark chocolate and seeds baked in a stream of golden honey and coconut oil; Vein of gold. Origin of something valuable or in great abundance.

  * e.g.,  ... "Oh my gosh! I just hit the mother lode!"