Appelo is a Dutch surname that originally indicated a person who was from a farm called Aperloo, a place name probably derived from the element appel meaning "apple". The name Aperloo itself may refer to a farmstead or hamlet, though the specific location is uncertain. The name is rare; Forebears data shows very few bearers worldwide. A variant form, Apperlo, exists with a similar etymology. Both forms originate from the same toponymic pattern common in Dutch surnames, where the suffix -loo means "clearing in the woods" (from Old Dutch *lauh*). Therefore, Appelo would describe someone who lived near an apple tree clearing. Such names were typically taken from a farm or locality in the eastern Netherlands.