Fussbox Share definition Flag Someone, typically a child, that will absolutely not stop screaming, crying, or fussing, no matter what you do to try to please them. Man, your kid won’t stop screaming! What a fussbox! Fussbox by fussbox September 7, 2023 0 0 Get merch Get the Fussbox mug. Buy Now — $32.95 See more merch