Gulf, Bay, Inlet
noun, suffix
The kanji and the word are exactly the same. That means they share meanings as well, though it contains some extra similar meanings as well, like a bay or inlet.
わん
Same reading as what you learned with the kanji.
伯父は、殺されて、ドラム缶の中でコンクリート詰めにされて東京湾に沈められました。
My uncle was killed, put in a concrete drum filled with cement, and sunk in Tokyo Bay.