goldmine has definitions from the fields of geology,work,mining
1
[ noun ] a sudden happening that brings good fortune (as a sudden opportunity to make money)

Examples

"the demand for testing has created a boom for those unregulated laboratories where boxes of specimen jars are processed like an assembly line"

Related terms

happening

2
[ noun ] a good source of something that is desired

Synonyms

gold_mine

Related terms

source

3
[ noun ] (geology,work,mining) a mine where gold ore is found

Synonyms

gold_mine

Related terms

mine

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