What is meant by n-fold axis of symmetry?

Explanation

### Step-by-Step Solution:

1. **Definition of n-fold Axis of Symmetry**:
An n-fold axis of symmetry refers to a characteristic of a molecule where it can be rotated around a central axis by a specific angle (360°/n) and still appear the same. This means that after each rotation, the molecule looks indistinguishable from its original form.

2. **Understanding the Concept**:
To illustrate this, consider a square. If you rotate the square by 90 degrees (which is 360°/4), it still looks like a square. This indicates that the square has a 4-fold axis of symmetry (n=4).

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