Mo. Rev. Stat. § 145.101: Definitions.

1. "Executor" means the executor or administrator of the decedent, or, if there is no executor or administrator, then any person in actual or constructive possession of any property of the decedent.

2. "Nonresident" means an individual who is not a resident.

3. "Resident" means an individual who is domiciled in this state at the time of death.

4. "State" means any state or territory of the United States and the District of Columbia.