Irbid, city, northwestern Jordan. The center of the country's most fertile agricultural region, it is also a developing industrial center. Yarmouk University (1976) is here. Irbid is identified with the ancient Beth-Arbel of the Bible. The city's rapid growth between 1950 and 1970 is, in part, due to the influx of refugees from the West Bank. Population (1994 estimate) 281,000.