gold rush

(noun) a sudden happening that brings good fortune (as a sudden opportunity to make money). Synonyms: boom, bonanza, gold rush, gravy, godsend, manna from heaven, windfall, bunce. Example: "The demand for testing has created a boom for those unregulated laboratories where boxes of specimen jars are processed like an assembly line."

(noun) a large migration of people to a newly discovered gold field. Synonyms: gold rush.