deathwad
A sandwich carried in a backpack with other objects until it is mashed into a nearly unidentifiable mass. Frequently used by people who work outside and carry their lunch with them, especially field archaeologists. Has its origin in the late 1970s in the Death Valley region of California, but the term is still regularly used today.
A peanut butter and jelly deathwad is much safer than a ham and cheese, especially on a hot day when the mayonnaise has gone clear.