Estuary \Es"tu*a*ry\, n.; pl. {Estuaries}. [L. aestuarium, from
aestuare to surge. See {Estuate}.] [Written also
{[ae]stuary}.]
1. A place where water boils up; a spring that wells forth.
[Obs.] --Boyle.
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2. A passage, as the mouth of a river or lake, where the tide
meets the current; an arm of the sea; a frith.
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it to the sea was often by long and wide estuaries.
--Dana.
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