Es″tu‐a‐ry (?), n.; pl.Estuaries (#). [L. aestuarium, from aestuare to surge. See Estuate.] [Written also æstuary.] 1. A place where water boils up; a spring that wells forth. 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. Dana.