Abu Dhabi, also spelled Abū Ẓaby, constituent emirate of the United Arab Emirates (formerly Trucial States, or Trucial Oman). Though its international boundaries are disputed, it is unquestionably the largest of the country’s seven constituent emirates, with more than three-fourths of the area of the entire federation. Its rich oil fields, both onshore and in the Persian Gulf, make it, with neighbouring Dubai, one of the nation’s two most prosperous emirates.

Abu Dhabi fronts the Persian Gulf on the north for about 280 miles (450 km). The desolate coast has many areas of sabkhah (“salt marsh”) and numerous offshore islands. Abu Dhabi borders Qatar (west), Saudi Arabia (south), and Oman, formerly Muscat and Oman (east). Internally it half surrounds Dubai and has a short frontier with Al-Shāriqah.