Top definition
A small pill made up of a compressed sponge inside a gel pill. When placed in water the casing dissolves, the sponge grows, and all delight! The sponge is often colored and cut into fun shapes, such as animals or dinosaurs.
I bought a pack of magic growing sponge egg toys for my kids, but they ate them all. They've been puking rainbow sponge dinos for hours.
by laserfeet April 15, 2009