Arlin is a name of uncertain origin, usually explained as a variant of Arlen or Arlan, which in turn is traced either to an Irish surname or to a Germanic root meaning "pledge" or "oath". It was a quiet rural American name in the early 20th century and is now also used in Hispanic families. Arlin is rare in the United States, peaking at number 2423 in 2024 and ranking number 2768 in 2025 with 46 births.