Elaborate the abbreviation : ERV.

Explanation

**Step-by-Step Text Solution:**

1. **Identify the Abbreviation**: The abbreviation ERV stands for "Expiratory Reserve Volume."

2. **Definition of ERV**: Expiratory Reserve Volume is defined as the maximum amount of air that can be exhaled after a normal exhalation.

3. **Understanding the Concept**: After a person exhales normally, there is still a certain volume of air that can be forcefully exhaled from the lungs. This additional volume is what we refer to as the Expiratory Reserve Volume.

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