A throne was a special type of chair upon which members of royalty or judges sit to conduct matters of judgment and have audiences with the public. It could also refer, metaphorically, to the position of power it represented.
In 2268, an insane "Lord" Garth of Izar instructed his minions to make his throne (actually an ordinary chair placed on top of a table) higher than anything else in the room. (TOS: "Whom Gods Destroy")
Q sat on a throne decorated with six lion sculptures while judging Captain Jean-Luc Picard and his crew in his recreation of a post-atomic horror courtroom. (TNG: "Encounter at Farpoint", "All Good Things...")
In 2373, an astonished Quark asked his mother if she was in reality the power behind Grand Nagus Zek's throne. She humbly replied that she only guided him a little in his decision-making. (DS9: "Ferengi Love Songs")