In
evangelical parlance, it can mean a "camp
meeting" - a nightly series of services. In
history, it has meant a mass outbreak of
belief, mass conversions of non-believers or
Christians whose
faith was
lukewarm. Often the effect dissipates after a while. Current ones in
Toronto and
Pensacola have gained fame.
In theatre, it's a new production of a classic work - Death of a Salesman on Broadway, for instance.
In pop culture, a retro thing, e.g. a glam revival.