Write a suitable term for the following description.
The fragrance of incense stick spreads in the entire space enclosed.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Description**: The question describes a situation where the fragrance of an incense stick spreads throughout an enclosed space. We need to identify the process that allows this fragrance to travel and mix with the air in the room.

2. **Identifying the Incense Stick**: An incense stick releases a pleasant fragrance when it burns. This fragrance is a type of gas that is produced during the burning process.

3. **Observing the Phenomenon**: When an incense stick is lit in one corner of a room, the fragrance does not stay in that corner. Instead, it spreads to the entire room, allowing people in different areas to smell it.

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