1. the time when the sun disappears below the horizon in the evening
2. the colors and light visible in the sky when the sun sets
3. the final period or decline of something
Usage: figurative

1. to come to an end or expire automatically
Usage: legal; formal

Examples

• We watched the beautiful sunset from the beach.
• The sunset painted the sky in shades of orange and pink.
• They planned to have dinner before sunset.
• The old law will sunset next year unless renewed.
• It was the sunset of his long career in politics.
• The sunset clause ensures the regulation expires in five years.