A metaphor is a figure of speech that compares two unrelated things or concepts, suggesting a similarity between them. In the given example, "At the end of the day, the sun is a freshly ripened orange," the speaker is using a metaphor to convey their perception of the sun. By comparing the sun to a "freshly ripened orange," they are highlighting certain qualities or aspects of the sun, such as its round shape, vibrant color, and the sense of warmth it provides similar to the feeling of biting into a ripe orange. This comparison allows the listener to visualize and understand the speaker's perspective on the sun.