Lagoon (noun) — بحيرة ضحلة: A shallow body of water separated from the sea by a reef or sandbank. Below are 8 words with a similar meaning; the linked ones have full GL Dictionary entries with their meaning in Arabic.
sea poolcoastal lakeatoll poolshallow bayinletmere
The tidal mouth of a large river where fresh water meets and mixes with salt water from the sea; a water passage where a river flows into the ocean.