This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
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adj. Remaining as an unused portion or amount.

n. A remnant or an unused portion.

n. Food remaining from a previous meal.

adj. Remaining; left behind; extra; in reserve.

adj. Remaining after a meal is complete or eaten for a later meal or snack.

n. Something left behind; an excess or remainder.

adj. not used up; remaining after use of part.

adj. remaining from a previous meal; -- of food.

n. An unused part or portion; -- used especially of food remaining uneaten from a previous meal.

adj. not used up

adj. not used up

n. a small part or portion that remains after the main part no longer exists

"I also engaged in leftover salvage to make twice-cooked pasta and a veggie cheese sauce."

unexhausted   

balance    remainder    residuum    residual    rest    residue   

left over(predicate)    left(predicate)    odd    remaining    unexpended    cooked-over    warmed-over    reheated    remnant   

half-eaten    canned    savory    uncooked    spicy    tasty    homemade    succulent    greasy    stale