Strange, unfamiliar, unknown, foreign, extraterrestrial, creature from outer space, space invader or Martian.
synonym I had this for class.
Sometimes, depending on what, it could be 'different.'
Alien Grays Little Green Men Martians
* alien * expatriate * nonnative * offshore * overseas
newcomer, outlander, foreigner, outsider, alien
different, unusual, new, untried, strange, alien
alien, exotic, unknown, strange, imported, remote, unfamiliar
That would be ALIAS; Alien Lifeform Intended for Assassination and Sabotage.
Strange, foreign, alien, outside, and extrinsic are all synonyms for extrinsic.
Synonyms: exterior, alien, foreign Antonyms: Inside, internal.
One synonym for the word "foreign" is "international." This term is often used to describe things that are from or relate to other countries.
Native is a word. A synonym would be another word that means the same thing, such as aborigine or perhaps inhabitant. An antonym would be a word meaning the opposite, such as alien or immigrant.