optional extra編輯正在努力提供更完整的內容，建議 20 分鐘後再回來看看optional extraoptional extra — 名詞名詞1. an additional item that can be added if desired but is not necessary1.名詞釋義選用配件an additional item that can be added if desired but is not necessary例句Leather seats are an optional extra on this car.