Oligarchy

Here are the definitions matched with the corresponding government types:

1. **Oligarchy** - A government in which a small group of people has control.

2. **Federal System** - A system of government where power is divided between a central authority and constituent political units (like states or provinces).

3. **Unitary System** - A system of government where power is concentrated in a central authority, and any administrative divisions exercise only powers that the central government chooses to delegate.

4. **Confederal System** - A union of sovereign groups or states that come together for certain common purposes, with the majority of power resting with the individual states rather than a central authority.

5. **Autocracy** - A government in which one person has absolute power and control (this matches your provided definition).

6. **Democracy** - A system of government in which power is vested in the people, who rule either directly or through freely elected representatives.

Let me know if you need further clarification!