, Ayutthaya Province, Thailand.]]A flood is an overflow of an expanse of water that submerges land, a deluge.MSN Encarta Dictionary. Flood. Retrieved on 2006-12-28. In the sense of "flowing water", the word is applied to the inflow of the tide, as opposed to the outflow or "ebb".It is usually due to the mass of water within a body of water, such as a river or lake, exceeding t