medieval northern Spanish kingdom, named for a river that runs through it, probably from a PIE root meaning "water." Related: Aragonese (late 14c., Arragounneys); Middle English also had as a noun Aragoner.
arable
arachnid
arachnoid
arachnologist
arachnophobia
Aragon
Aramaean
Aramaic
araneology
arational
Araucanian