The term 'CHILD'S APPLIANCE' can be solved by the four-letter word 'OVEN'. An OVEN is a kitchen appliance used for baking, roasting, and heating food. It is often used to cook meals such as cakes, pies, and casseroles. Ovens are also used to heat up leftovers or to reheat pre-cooked meals. Ovens are a common appliance in many households, and they are especially popular with children who enjoy baking and cooking.