Rainbow Ponies! Share definition Flag An exclamation of joy, also something to break awkard silences. "You just won a million dollars!" "RAINBOW PONIES!" also- "I farted." "Rainbow Fricking Ponies!" Rainbow Ponies! by NLT (the boy band!) lover May 12, 2008 0 0 Get merch Get the Rainbow Ponies! mug. Buy Now — $32.95 See more merch