Alien is a girl name. It last appeared in U.S. Social Security records in 1933. Alien first appears in the data in 1924 and reached its peak in 1924 (6 births). The chart below shows how the name has risen and fallen over time.
How popular is Alien? (U.S. births per year)
U.S. births per year, 1924–1933 · hover or tap for the count and national rank · source: U.S. Social Security Administration