Third-person singular simple present indicative form of sour.(verb)
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Use "sours" in a sentence
"Even though the name sours on my tongue, I say, “God says so.”"
"That sounds very civilized (provided no one drinks way too many amaretto sours, that is!)."
"If anything, crime – and the demand for sufficient law enforcement – is more likely to increase when the economy sours, which is also when public revenues dip."