aliens >> /ˈeɪlɪən/
Definition: [noun] A foreigner, especially one who is not a naturalized citizen of the country where he or she is living.
Example: an enemy alien
Definition: [noun] A hypothetical or fictional being from another world.
Example: she discovers that the alien's spaceship has crashed
Definition: [adjective] Belonging to a foreign country.
Example: an alien culture
Definition: [adjective] Unfamiliar and disturbing or distasteful.
Example: principles that are alien to them
Definition: [adjective] Supposedly from another world; extraterrestrial.
Example: alien beings