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. [Obs.] 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.

Es"tu*a*ry, a. Belonging to, or formed in, an estuary; as, estuary strata. Lyell.

• Coastal water body where ocean tides and river water merge.
  
• An ocean inlet also fed by fresh river water.