请问reciprocal是什么意思？

²reciprocal
        ²    n.

        
            
                
                    
                    
                
                    
                    

Function:	noun
Date:	1570

1
        : something in a
reciprocal relationship to another
2
        : either of a pair of
numbers (as 2/3 and 3/2 or 9 and 1/9) whose product is one broadly
        :
MULTIPLICATIVE
INVERSE