The reciprocal of  $\frac{1}{a}$, where  a $\ne$0, is 

Reciprocal : For any two rational numbers a, b if $a\times b=b\times a=1$ then a and b are said to be reciprocals of each other.

The reciprocal of  $\frac{1}{x}$ is $x$ 

 The reciprocal of  $\frac{1}{a}$ is  $a$ where  a $\ne$0