n. pl. es·tu·ar·ies
1. The part of the wide lower course of a river where its current is met by the tides.
2. An arm of the sea that extends inland to meet the mouth of a river.
[Latin aestuārium, from aestus, tide, surge, heat.]
es′tu·ari·al (-ârē-əl) adj.
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Indo-European & Semitic Roots Appendices
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