/ˌdɪsɛmˈbəʊɡ//ˌdɪsɪmˈbəʊɡ/
verb
disembogues, disembogued, disemboguing
[no object]
rare
(of a river or stream) emerge or be discharged into the sea or a larger river.
Origin
Late 16th century: from Spanish desembocar, from des- (expressing reversal) + embocar ‘run into a creek or strait’ (based on boca ‘mouth’).
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To be a tributary is to disembogue. It is a part of the natural "downhill" flow of things. But, looking at the confluence of the Mississippi River and the Ohio River, you might wonder which one was the tributary.
