**The word 'tart' means: Sour or Acidic**

**Explanation:**

Tart is a culinary term primarily used to describe a taste sensation in food and beverages. It refers to a sour or acidic flavor that can be found in certain fruits, desserts, and even savory dishes. Let's delve into the details of what the word 'tart' signifies:

**1. Sour or Acidic Flavor:**
The primary meaning of the word 'tart' is a flavor that is sour or acidic. When we say something is tart, we are indicating that it has a sharp, tangy taste that stimulates the taste buds. This flavor profile is commonly associated with fruits that possess a high acidity level, such as lemons, limes, oranges, and cranberries.

**2. Tart as a Dessert:**
In culinary terms, a tart can also refer to a specific type of dessert. A tart is a pastry-based dish with a shallow crust, filled with various ingredients such as fruits, custards, creams, or savory fillings. Often, the filling in a tart has a slightly tart or acidic flavor, which contrasts with the sweetness of the crust.

**3. Tartness in Savory Dishes:**
While the term 'tart' is predominantly associated with desserts, it can also be used to describe certain savory dishes. In this context, tart refers to a dish that incorporates acidic ingredients or flavors. For instance, a savory tart might feature ingredients like tomatoes, vinegar, or citrus fruits to add a tangy element to the dish.

**4. Contrast with Sweetness:**
Tartness is often used to provide a balance or contrast to sweetness. In desserts, the tart flavor can cut through the richness of sweet ingredients, creating a more complex and enjoyable taste experience. Similarly, in savory dishes, tartness can add a refreshing and bright quality that complements other flavors.

In conclusion, the word 'tart' primarily signifies a sour or acidic taste sensation found in fruits, desserts, and savory dishes. It is associated with flavors that are tangy, sharp, and have a certain level of acidity. Whether referring to a specific taste or a type of dessert, 'tart' is an essential culinary term used to describe a distinct flavor profile.