If you mean the Dragonmere, it is an arm of the sea, a "long bay" or arm of the Sea of Fallen Stars/Inner Sea. "Lake of Dragons" is the most popular name for it, but is fanciful, originating in a bard's ballad about dragons.
#realmslore
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Spik3
@Spike_4247
@TheEdVerse Me and my friends got into an argument lately. Is "Lake of Dragons" actually a lake, or already a part of the sea? We can't get to agreement on this topic.