Toast is sliced bread about 1 inch thick that has been browned by exposure to radiant heat.
This browning is the result of a Maillard reaction, altering the flavor of the bread as well as making it firmer so that it is easier to spread toppings on it.
Toasting is a common method of making stale bread more palatable.
Bread is often toasted using a toaster, an electrical appliance with heating elements.
Toaster ovens are also used for toasting bread. (source)
So can hamsters eat toast?
Toast is fine for them to eat. As long as it doesn’t have any other ingredients added to it or flavorings.