"one of the native people of Arabia and surrounding regions," late 14c. (Arabes, a plural form), from Old French Arabi, from Latin Arabs (accusative Arabem), from Greek Araps (genitive Arabos), from Arabic 'arab, indigenous name of the people, perhaps literally "inhabitant of the desert" and related to Hebrew arabha "desert."
Meaning "homeless little wanderer, child of the street" is from 1848 (Arab of the city, but the usual form was city arab), in reference to the nomadic ways of the Bedouin. Arab League formed in Cairo, March 22, 1945.
variant of suffix -an (q.v.), with connective -i-. From Latin -ianus, in which the -i- originally was from the stem of the word being attached but later came to be felt as connective. In Middle English frequently it was -ien, via French.
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Definitions of Arabian from WordNet
a member of a Semitic people originally from the Arabian peninsula and surrounding territories who speaks Arabic and who inhabits much of the Middle East and northern Africa;