Leftover refers to:

1. Something that remains unused or unconsumed, especially food served at a later meal. ^{merriam-webster.com 1}
2. An anachronistic survival or vestige. ^{merriam-webster.com 1}
3. A part of something that has not been used or eaten when other parts have been. ^{cambridge.org 2}
4. Food remaining uneaten at the end of a meal, especially when saved for later use. ^{dictionary.com 3}
5. Anything left or remaining from a larger amount; remainder. ^{dictionary.com 3}