cum vault Share definition Flag Noun - A worth while place to deposit ones semen. Most likely a smart, attractive, athletic and wealthy girl. Noun - "That girl is perfect, I'd love her to have my kids?" - "Ya, she'd make a good cum vault." cum vault by Butt-nut January 19, 2007 0 0 Get merch Get the cum vault mug. Buy Now — $32.95 See more merch