million-dollar question

Meanings

1. A question that is very important, difficult to answer, or (especially) both.
2. Used other than figuratively or idiomatically: a question to be decided, on whose answer depends a million-dollar expenditure.

Etymology

This collocation and its idiomatic meaning both long predate the TV game show Who Wants to Be a Millionaire?, whose last question involves a top prize of $1,000,000. They also predate the sixty-four thousand dollar question, which came from a TV game show that started in 1955 but clearly was itself influenced by similar existing constructions, including million-dollar question, which had this sense by 1927 at latest. The corpus shows that a burst of heightened popularity for such constructions occurred in the 1940s because of the radio program Take It or Leave It, which contained a sixty-four dollar question. All such collocations naming expensive questions seem to have their ultimate origins in literal instances (with various price tags) as managerial and public-debate issues; various examples of those are seen in publications from the 1910s.