What is define supplemental?

Supplemental is an adjective that refers to something that is additional or extra, beyond what is required or expected. It can be used to describe resources or materials that are provided as an addition to something else, such as a supplemental textbook or a supplemental income. In some contexts, it may also refer to a type of insurance or other financial product that provides additional coverage or benefits beyond what is included in a primary policy or plan. Overall, the term "supplemental" is used to convey the idea of something that is optional, but may be useful or beneficial in certain situations.