gold rush vs bonanza

gold rush and bonanza both are nouns.

Word	Noun	Adjective	Verb	Adverb
gold rush	Yes	No	No	No
bonanza	Yes	No	No	No

As nouns, gold rush and bonanza are synonyms defined as:

gold rush and bonanza: a sudden happening that brings good fortune (as a sudden opportunity to make money)

Other synonyms of gold rush include boom, bunce, godsend, gravy, manna from heaven, windfall.

gold rush (noun)	bonanza (noun)
a large migration of people to a newly discovered gold field	a sudden happening that brings good fortune (as a sudden opportunity to make money)
a sudden happening that brings good fortune (as a sudden opportunity to make money)	an especially rich vein of precious ore