Tyrant (noun)

A ruler who exercises power in a cruel and oppressive way, especially a dictator who has seized power by force.

Origin:

Middle english: from old french tyrant, from latin tyrannus, from greek turannos, from turas (genitive turannos) "power, rule".

Examples:

1. He was overthrown by the people who were tired of living under a tyrant.
2. The country was ruled by a tyrant who suppressed any dissent.
3. The tyrant was feared by all.
4. The tyrant's regime was marked by human rights abuses.
5. The tyrant was finally removed from power by a popular uprising.