1861, originally as the name of a breakaway Confederate region of southern New Mexico; organized roughly along modern lines as a U.S. territory in 1863, admitted as a state 1912. From Spanish Arizonac, which is probably from a local name among the O'odham (Piman) people meaning "having a little spring." Alternative theory is that it derives from Basque arizonak "good oaks."
arithmancy
arithmetic
arithmetical
arithmocracy
arithmomania
Arizona
ark
Arkansas
arm
armada
armadillo