Tzatziki, cacık, or tarator is a dip, soup, or sauce found in the cuisines of Southeast Europe and the Middle East. It is made of salted strained yogurt or diluted yogurt mixed with cucumbers, garlic, salt, olive oil, sometimes with vinegar or lemon juice, and herbs such as dill, mint, parsley and thyme. It is generally served as a cold appetizer (mezze) or a side dish.

Tarator was the name of a dish made of ground walnuts and vinegar in the medieval Ottoman Empire. Dishes of various preparations in the region, including dips, salads, and sauces, acquired the name. In the Levant, taratur is a sauce based on tahini, while in Turkey and the Balkans it came to mean a combination of yogurt and cucumbers, sometimes with walnuts. It has become a traditional part of meze.

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