Chumsicle is a food item that appears in the episode "Shopping List."
It is essentially Plankton's chum in popsicle form.
Role in episode
When Plankton fails to get milk from a fangtooth fish, he ends up making her angry. Plankton attempts to get out of trouble by offering her a chumsicle, but the fangtooth fish whacks it away and attacks him by spraying her milk at him.
Plankton gets the milk, but ends up getting swallowed by another fangtooth fish.