Baor  dead arm of a river in the Moribund Delta as in the case of the ganges; also called oxbow lake. It appears as a saucer shaped depression. The term baor is synonymous to beel, familiar in the southwestern part of Bangladesh. The notable baors of the country are Sagarkhali, Jaleshwar, Khedapara, Rampur, Pathanpara, Kathgara, Jogini Bhagini, Ichamati, Joydia, Marjat, Harina and Arial. They range in size from half a square kilometre to 13 sq km. Baors are more stagnant than beels and generally have water throughout the year. The most common view regarding its origin is that when a river changes its course some of its sections at the supply source get silted-up, cuts off the arms, and develops an oxbow lake called baor.

Baors receive water only when the parent river is in high flood. Usually, during the wet season a baor receives local rainwater. At times, the accumulated water may spill over from the adjacent floodplain and may cause local flooding. Baors are considered to be very important wetlands of Bangladesh and support a wide range of aquatic lives (flora and fauna). Relatively higher peripheral land along the baors are used for cultivating paddy and for grazing livestock. [Mohd Shamsul Alam]