The term 'APPLE LEFTOVER' can be broken down into three crossword solutions: CORE (4 letters), ASH (3 letters), and REMNANT (7 letters). CORE refers to the innermost part of an apple, which is usually composed of seeds and a fibrous material. ASH is a type of residue that is left behind after something has been burned or destroyed. Finally, REMNANT is a term used to describe something that is left over after the majority of it has been used or consumed.