Aeon

Regos Krang stated that Mondas and Earth were twin planets aeons ago. (TV: The Tenth Planet)

The Second Doctor noted that he had aeons of time to explore. (TV: The War Games)

According to Andred, Rassilon died aeons ago. (TV: The Invasion of Time)

The Logopolitans held back entropy for aeons. (TV: Logopolis)

According to Toby Zed, Krop Tor supported life aeons ago. (TV: The Impossible Planet)

Gavrok earned his reputation in "a few short aeons." (PROSE: Delta and the Bannermen)

The universe had undergone aeons of expansion by the time of its end. (PROSE: Timewyrm: Apocalypse)