When a male grabs the lower portion of his scrotum with both hands, pulling it out and upward towards himself, leaving his cock sticking out like a "marsupial in the pouch". Ususally for the entertaiment of others.
The dinner party ended when john pulled down his pants and did the "marsupial".
by B*rad August 10, 2007
Marsupials are small mammals that are attached to the male body and as in the animal kingdom spend most of their life in a pouch. Only jumping out to surprise people!
When i crouched down to pick something up off the floor with my shorts on, my marsupials popped out!
by Jason Houghton March 13, 2007