Testamentary
A testator (/tɛsˈteɪtɔːr/) is a person who has written and executed a last will and testament that is in effect at the time of his/her death. It is any "person who makes a will."
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Wikipedia
A testator (/tɛsˈteɪtɔːr/) is a person who has written and executed a last will and testament that is in effect at the time of his/her death. It is any "person who makes a will."