Estuary
Estuary , noun
[Latin aestuarium, from aestuare to surge. See Estuate.]
1.
A place where water boils up; a spring that wells forth. [Obsolete] — Boyle
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.
Estuary , adjective
Belonging to, or formed in, an estuary; as, estuary strata. — Lyell