noun

• (historical) A fence of the type once commonly improvised in northeastern Africa from thornbushes.
  "On the left shore two neat farmyards shew themselves in a shining seriba of reeds, the stalks of which are connected very regularly with each other, but perhaps only afford resistance to tame animals."
• (by extension) An improvised stockade, particularly those similarly located and constructed.
  "The Black Watch (Royal Highlanders) advanced this morning to Baker Pasha’s zariba."
• (by extension) A camp of troops employing such an enclosure.
  "[…] forming a zariba, or square, to resist cavalry."
• (by extension) Any wild and barbed barrier, evocative of a briar or thorn patch.
  "Once you had passed the initial zareba of fruit stands, souvenir stands, ice-cream stands, and the lair of the enthusiast whose aim in life it was to sell you picture postal-cards, and had won through to the long walk where the seats were, you were practically alone with Nature."