Ephemeral

Ephemeral was the term used by immortal creatures to refer to mortal beings in any time on any planet in any galaxy. Being immortal and dwelling outside the realm of time, the Eternals regarded both humans and Time Lords as Ephemerals, lesser beings they used for their own purposes like toys. (TV: Enlightenment)

Some Eternals posed as gods and doomed whole planets for their amusement. Under certain exceptional circumstances, sometimes against their will, an Eternal might enter the realm of the Ephemerals permanently, prey to age and death. (COMIC: Uninvited Guest)

The Aquillians, who claimed to be immortal, also regarded humanity and the Seventh Doctor as Ephemeral. (AUDIO: Signs and Wonders)

The Trickster described Sarah Jane Smith as "Ephemeral." (TV: Whatever Happened to Sarah Jane?)

Rakaya asked Zellin if he had any idea how it must feel for humans to be "tiny, Ephemeral flashes of existence". (TV: Can You Hear Me?)