Liman (Лиман) is a Hellenized Russian adaptation of the Medieval Greek λιμένας (limenas) meaning bay or port. The term is usually used in place of the more universal delta, with its implication of landform, to describe wet estuaries in the Black Sea and the Sea of Azov. A synonymous term guba (губа) is used in Russian sources for estuaries of the Russian shores in the north. A liman is formed at the widening mouth of a river, where flow is blocked by a bar of sediments. Liman can be maritime (the bar being created by the current of a sea) or fluvial (the bar being created by the flow of a bigger river at the confluence).