alien
US /ˈeɪ.li.ən/
UK /ˈeɪ.li.ən/

1.
extranjero, alienígena
a foreigner, especially one who is not a naturalized citizen of the country where they are living
:
•
The government has strict laws regarding alien residents.
El gobierno tiene leyes estrictas con respecto a los residentes extranjeros.
•
He felt like an alien in his new school.
Se sentía como un extraño en su nueva escuela.
2.
alienígena, extraterrestre
a hypothetical or fictional being from another world; an extraterrestrial
:
•
The movie featured a friendly alien.
La película presentaba un alienígena amigable.
•
Scientists are searching for signs of alien life.
Los científicos están buscando signos de vida alienígena.
1.
ajeno, extraño
unfamiliar and disturbing or distasteful
:
•
The concept of absolute freedom was alien to him.
El concepto de libertad absoluta le era ajeno.
•
His behavior was completely alien to his usual character.
Su comportamiento era completamente ajeno a su carácter habitual.
2.
extranjero, ajeno
belonging to a foreign country or nation
:
•
The company deals with alien currencies.
La empresa trabaja con monedas extranjeras.
•
They discussed the impact of alien cultures on local traditions.
Discutieron el impacto de las culturas ajenas en las tradiciones locales.