.......................................is the exudation of water drops from the tip or margins of lamina at the vein ends.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Process**: The question asks about the exudation of water drops from the tips or margins of the leaf lamina at the vein ends. This process involves the release of water in liquid form.

2. **Identifying the Term**: The specific term used to describe this phenomenon is "guttation." Guttation refers to the loss of water in the form of liquid droplets from the plant.

3. **Mechanism of Guttation**: The process of guttation occurs through specialized structures known as hydathodes. These are pores located at the leaf margins and tips that facilitate the exudation of water.

...