busted flush

/B AH1 S T IH0 D F L AH0 SH/
noun
  1. 1

    A potential flush which ultimately was not filled.

    โ€œI thought I'd draw another spade, but I ended up with a busted flush.โ€

  2. 2

    Anything which ends up worthless despite great potential.

Source: https://en.wiktionary.org/wiki/busted%20flush