Estuary /(?)/

pl. Estuaries

1. A place where water boils up; a spring that wells forth. [Obs.]
2. A passage, as the mouth of a river or lake, where the tide meets the current; an arm of the sea; a frith.

   it to the sea was often by long and wide estuaries.

1. Belonging to, or formed in, an estuary; as, estuary strata.