- The act of appearing.
- Outward or visible aspect of a person or thing. It is a physical property of matter, meaning that a change in chemical composition does not necessarily cause a change in appearance.
- The event of coming into sight. When you first see something, the thing is said to have appeared. Inversely, when the thing goes out of sight, the thing is said to have disappeared, dis- being a Latin root meaning 'not'.
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