There is a significant difference between the meaning of the word “property” in a will and the meaning of “residue of the estate”.
First, with respect to property, there are two types of property in law. There is “real property”, being land. And there is “personal property”, being money in the bank, stocks, RRSPs, cars, and so forth.
The “residue of the estate" refers to what is left over to distribute after the executor pays out the expenses, debts and taxes the deceased person has to pay, as well as any specific gifts made in the will. So for example, let's say a will provides a gift to a grandchild of $25,000. The residue of the estate is what is left over after the executor pays the estate expenses, debts and taxes, as well as the $25,000 gift to the grandchild. The gift to the grandchild is a transfer of “property” to that beneficiary.
There is typically a residue in any estate. That is partly because nobody can know for certain, when making a will, what property they will own when they die.