Halloween Special - Aliens

There are several Japanese word for out-world denizens, but here are some of the most common ones considering the pertinent season that we are in.

SEIJIN (星人)

Literally "star/planet person", this works as a generic suffix for extraterrestrials from various planets, such as ナメック星人 (Namekku-seijin) for the slug-like people of Namek in the cartoon series Dragon Ball, likewise more generally a Martian would be a 火星人 (kaiseijin), where the planet's name is 火星 (kasei, lit. "fire star/planet" - itself stemming from ancient Chinese astrology).

ISEJIN (異星人)

The first kanji literally means "strange/unusual" or more usually "other/different" hence "person from another planet", this mirrors 異国 (ikoku, "foreign country"). The term 異星 (isei, "different planet") also exists.

UCHÛJIN (宇宙人)

"Space person" or "cosmic person", the regular term to translate the English term extraterrestrial or E.T. This term is far more common in science fiction, when talking about the diminutive verdant fellows from yonder worlds.

EIRIAN (エイリアン)

Literally a spelling of the English word "alien" into the katakana system. This is also used as the name for the Xenomorphs of that famous series of science fiction films. This term has a bit of a more international flair.