Sweetener (noun)

1. A substance added to food or drink to make it sweet.
2. A person or thing that adds charm or appeal to something.

Origin:

From the old english word "swetian", meaning "to make sweet".

Examples:

1. Aspartame is a common sweetener used in diet sodas.
2. The addition of fresh mint leaves served as a sweetener to the fruit salad.
3. He was a natural sweetener in any social setting.
4. She added a dash of maple syrup as a sweetener to her oatmeal.
5. The new car's features acted as a sweetener in the negotiations.