The main, central lode of a natural resource, near which smaller deposits of the same ore etc. exist.(noun)
The main prize, best cut or pick etc. by far, dwarfing all others.(noun)
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Use "motherlode" in a sentence
"US intelligence network aims to put heat on al-Qa'ida US intelligence will seek to achieve in the coming weeks "information dominance" over the al-Qa'ida network - taking advantage of what officials have called a "motherlode" of data found at Osama bin Laden's compound in Abbottabad."
"While hedge funds target what Marathon Asset Management LP co-founder Bruce Richards calls the "motherlode" of distressed investing, insurers are focusing on forced sales of higher- quality, longer-term assets, such as mortgage loans."
"This is what you might call the motherlode location when it comes to kid-friendly activities."