nm. estuary, place where the river current meets the sea tide (as in the mouth of a river)

nm. estuary, place where the river current meets the sea tide (as in the mouth of a river); firth, narrow arm of the sea (Scottish)

n. estuary, firth; frith

(n.) = estuary.
Ex: A search of the term 'shellfish' selects a further 126 terms, of which the six most highly ranked are: oysters, mussels, clams, tides, estuaries, and seafoods.