Answer: “It’s an egg separator. They work very well if the hole is cut properly. Crack a whole egg into the cup/bowl, and then tip it over a container to catch the white as it pours out of the slot. The yolk, if not broken, will stay neatly in the separator.”
Corn Remover. Cut the kernels from the cob.
It's for both. Also good for squeezing citrus, cracking eggshells, and breaking bones. Not everything has ONE purpose.
It's both, and good on crab... although with lots of crab/lobster consumed a person gets good enough not to need anything but teeth.