The words “tyranny” and “despotism” are often used interchangeably. John Locke, however, defined them differently. In his Two Treatises of Government, he wrote:
“…tyranny is the exercise of power beyond right…”
…and…
“Despotical power is an absolute, arbitrary power one man has over another, to take away his life, whenever he pleases.”
According to these definitions, tyranny does not necessarily imply despotism. One can exercise “power beyond right” without enjoying total power. A ruler may be able to get away with some tyrannical encroachments, but not others. And power that is checked is not absolute and therefore not “despotical” according to Locke’s definition. However, the more tyranny a government can perpetrate, the closer to absolute power it gets.
Similarly, despotism does not necessarily mean tyranny in theory; however, it invariably does in practice. Tyranny, per Locke, is not a matter of holding power beyond right, but exercising it. Someone who holds absolute power could conceivably refrain from wielding it. But no despot in history ever has. Absolute power corrupts absolutely, after all.