- boom, bonanza, gold rush, gravy, godsend, manna from heaven, windfall, bunce - a sudden happening that brings good fortune (as a sudden opportunity to make money); "the demand for testing has created a boom for those unregulated laboratories where boxes of specimen jars are processed lik an assembly line"
--1 is a kind of happening, occurrence, natural event
- gold rush - a large migration of people to a newly discovered gold field
--2 is a kind of migration