Final answer:
The arrangement in which co-owners receive the property share of a deceased co-owner is known as a right of survivorship, commonly associated with joint tenancy.
Step-by-step explanation:
If Bill, Steve, and Mona agreed that if one of them died, the others would receive their share of the Adirondack camp, this arrangement is typically known as a right of survivorship. It is commonly found in joint tenancy agreements, where co-owners have an equal share in the property, and upon the death of one, their share automatically transfers to the surviving co-owners. This process bypasses traditional inheritance procedures and is separate from matters outlined in a will or estate planning.