What is the significance of the word average in the definition of atomic mass ?

Explanation

### Step-by-Step Solution:

1. **Understanding Atomic Mass**:
- Atomic mass is defined as the weighted average of the masses of all the isotopes of a particular element.

2. **Definition of Isotopes**:
- Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses.

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