Arlan is a variant of Arlen or Arlin, a name of uncertain origin that is usually explained as an English surname or as a form of the Irish Gaelic word for "pledge" or "oath". It has a lean, old-fashioned American sound that fits with Harlan and Arlo. Arlan has risen from number 6350 in 2000 to number 2392 in 2025, its best rank in the United States so far.