1. Literally (of fruit), to shrivel and die before being harvested, due to neglect or lack of resources. With the horrible drought we've had this summer, nearly all of the fruit in my orchards died on the vine. You forgot to water my tomato plant! Now they've all died on the vine!

2. By extension, to fail prematurely or not come to fruition, as due to being ignored, neglected, impractical, or without the necessary means to succeed. The president made sweeping promises during his campaign, but many of those have died on the vine. Many of the resources for students with learning disabilities have died on the vine following the school board's budget cuts.