: having an acid taste that is like the taste of a lemon
: having the unpleasant taste or smell of food that is no longer fresh
: unpleasant or unfriendly
: an alcoholic drink that has a sour taste
of food : to lose freshness and get an unpleasant taste or smell : to become sour
: to become unpleasant or unfriendly
: to make (someone or something) unpleasant or unfriendly
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