Xenomorph is the commonly used species name for the creature called the Alien in the Alien film franchise.
The original 1979 film, Alien, does not generally present “Xenomorph” as the creature's formal species name in spoken dialogue. The word comes from Greek roots meaning foreign form and became widely used by characters, expanded-universe material, fans, and promotional references.
The creature was designed by Swiss artist H. R. Giger, whose biomechanical artwork shaped its distinctive appearance. Its life cycle includes the egg, facehugger, chestburster, and adult stages. The reproductive process is one of the franchise's most recognizable horror concepts.
“Xenomorph” is often treated as a specific proper name, but it is better understood as a descriptive label. The films also use terms such as “the creature” and “the organism,” while different forms and related species appear across the wider franchise.