(æb)  [Arab. ab'.] 

    A sleeveless outer garment, resembling a sack with openings for the head and arms, worn by Arabs.
 
  1811 tr. Niebuhr's Trav. Arab. cxxii, in Pinkerton Voy. X. 156 A blind tailor at Basra, who earned his bread by making Abbas. 1833 A. CRICHTON Hist. Arabia II. v. 193 A silk gown, over which is thrown a white abba of the finest manufacture of El Hassa. Ibid. viii. 350 The common abba is without sleeves, resembling a sack, with openings for the head and arms. 1880 L. WALLACE Ben-Hur VIII. iv. 496 Galileans in his league, carrying short swords under their long abbas. 1934 F. STARK Valleys Assassins ii. 74, I enveloped myself in the brown abba, tightly pinned under the chin. 1942 M. HOME House of Shade iii. 54 Over it was an aba, or sleeveless coat of fine linen.