Most resembling or containing broth; having the greatest amount of broth-like qualities among things being compared.
From broth plus -y suffix (adjective-forming) plus -est for superlative form. The same root as brothier but in its most extreme form.
Medieval cooks would have needed words like this to describe broths of different consistencies—the brothiest ones were probably the richest, most flavorful, since they had the most dissolved solids from long simmering.
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