took a dive

Verb

take a dive (third-person singular simple present takes a dive, present participle taking a dive, simple past took a dive, past participle taken a dive)

1. To decline rapidly.
   • Other broad market gauges took even steeper dives, with the Standard & Poor's 500, which includes financial stocks, falling 9.93%.2008 December 1, John Curran, “The Recession Is Made Official — and Stocks Take a Dive”, in Time
2. (idiomatic) To feign a knockout in order to lose intentionally.
   • I decided there could be a nice bit of irony in a situation where a boxer, with a crown his for the taking, deliberately takes a dive to get revenge on the man he hates, who is betting everything on the boxer's victory.1950, Jules Archer, I Sell What I Write, page 44
3. (idiomatic) To lose or fail intentionally.