Earthling

Earthlings (also known as Earthers or Gaians, or Terrans) are inhabitants of planet Earth. The word is first attested in this sense in the 1590s, and was used in science fiction as early as 1949, in "Red Planet" by Robert A. Heinlein.
History.
Historically, the term "earthling" referred to a mortal inhabitant of the Earth as opposed to spiritual or divine entities. In Early Modern English, the word was used with the intention of contrasting "earth" with "heaven", and so presenting man as an inhabitant of the sublunary sphere, as opposed to heavenly creatures or deities. The derivation from the noun "earth" by means of the suffix "-ling" is already seen in Old English "yrþling", in the meaning "ploughman". The sense of "inhabitant of earth" is first attested in the 1590s. It was used in science fiction as early as 1949, in "Red Planet" by Robert A. Heinlein.
The word "man" and "human" has the same imposed meaning, since it originates from a Proto-Indo-European word "*ǵʰmṓ" "earthling" < "*dʰéǵʰōm" "earth". Compare Latin "homo" "human" and "humus" "earth, soil".
Modern use.
Its modern use in science fiction literature contrasts Earth (the planet) with outer space or hypothetical other planets with sapient life. The term was often used in 1950s science fiction film and novels by aliens to express a disdainful or patronizing tone towards creatures from Earth. The meaning "creature from planet Earth" in the context of space travel may be extended to non-human species, as in "Russia fetes dog Laika, first earthling in space".
In some science fiction media (such as the "Star Trek" franchise and the 2014 movie "Guardians of the Galaxy") the term "Terran" is used as a term for humans, stemming from "terra", the Latin word for Earth. Others, such as The Expanse, use the word "Earther." In the original run of the BBC series "Doctor Who", the phrase "tellurian" is used.