In ferns like pteris leaf is called frond.

Explanation

**Step-by-Step Solution:**

1. **Definition of Frond**: In ferns, the leaf is specifically referred to as a "frond." This term is used to describe the large, complex leaves characteristic of ferns.

2. **Structure of Fronds**: The fronds of ferns are generally large and have a significant surface area. This large size is one reason they are categorized as "megaphylls," which means "large leaves."

3. **Venation Pattern**: The venation, or the arrangement of veins within the fronds, is distinct in ferns. Ferns exhibit an "open furcate" venation pattern, meaning the veins branch out in a way that is different from the typical patterns seen in other plants.

...