Residual sugar

Residual sugar is what remains when yeast have not eaten all the grape sugar in Must. Dry wine is not zero molecules; it is below the threshold where most tasters call the wine sweet. Sweetness is a taste. Acidity and Tannin change how much sugar you notice — tannin's astringency is still a tactile binding of saliva protein, not a sugar ¹.

Legal “dry” definitions vary by jurisdiction and wine type. The tasting consequence belongs here: Wine fermentation is the process that consumes sugar, while Tasting wine is where you describe sweet, sour, bitter, and dry without a scorecard.

If fermentation stuck, you have a cellar problem and a sweetness you did not plan. If fermentation was stopped, you have a style. Taste against acid, not against a slogan.