A number or symbol, often written as a subscript or superscript to a mathematical expression, that indicates an operation to be performed on, an ordering relation involving, or a use of the associated expression.是什么意思_A number or symbol, often written as a subscript or superscript to a mathematical expression, that indicates an operation to be performed on, an ordering relation involving, or a use of the associated expression.在线翻译_英语_读音_用法_例句