The term MERINGUE INGREDIENT is composed of three crossword solutions: EGG (3 letters), EGGWHITE (8 letters), and EGGWHITES (9 letters). All three solutions refer to the same ingredient, which is a key component of meringue. Eggs are a necessary ingredient for meringue because the EGG whites provide the structure and stability needed for the meringue to hold its shape. EGG whites are also used in meringue because they contain proteins that help the meringue to form a stiff foam when whipped. EGG whites can be used alone or in combination with other ingredients to create a variety of meringue recipes.