Gastric folds are called rugae/villi.

Explanation

**Step-by-Step Solution:**

1. **Understanding Gastric Folds**: Gastric folds are structures found in the stomach. They are known as rugae, which are folds of the stomach lining that allow the stomach to expand when filled with food.

2. **Distinguishing Between Rugae and Villi**: Villi, on the other hand, are small, finger-like projections found in the small intestine, specifically in the jejunum and ileum. They increase the surface area for absorption of nutrients.

3. **Identifying the Correct Term**: The question asks whether gastric folds are called rugae or villi. Since rugae are the folds in the stomach and villi are projections in the small intestine, the correct answer is that gastric folds are called rugae.

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