fizzled out Share definition Flag When a person ends a relationship by stopping communication/caring. Cowardly way to avoid drama. Gi: So what ever happened to you and Karl? Veronica: Oh, we kind of just fizzled out. fizzled out by Williaem September 19, 2010 0 0 Get merch Get the fizzled out mug. Buy Now — $32.95 See more merch