"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.
word-forming element in names of countries, diseases, and flowers, from Latin and Greek -ia, noun ending, in Greek especially used in forming abstract nouns (typically of feminine gender); see -a (1). The classical suffix in its usual evolution (via French -ie) comes to Modern English as -y (as in familia/family, also -logy, -graphy). Compare -cy.
In paraphernalia, Mammalia, regalia, etc. it represents Latin or Greek -a (see -a (2)), plural suffix of nouns in -ium (Latin) or -ion (Greek), with formative or euphonic -i-.
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Definitions of Arabia from WordNet
a peninsula between the Red Sea and the Persian Gulf; strategically important for its oil resources;