The negative of a rational number $\frac{-1}{2}$ is _____.

A negative rational number is a rational number that is less than zero. It can be expressed as the ratio of two integers, such as a/b where a and b are integers and b is not equal to zero. It is represented by a negative sign (-) in front of the number. 

Therefore, the negative of a rational number$\frac{-1}{2}$ is $-\left(\frac{-1}{2}\right)=\frac{1}{2}$.