Let \( x \) represent the original price of the shirt. According to the problem, the sale price of the shirt, which is $7.98, is half of the original price. This can be expressed with the following equation:
\[ \frac{x}{2} = 7.98 \]
To solve for \( x \), multiply both sides of the equation by 2:
\[ x = 7.98 \times 2 \]
Calculating the right side:
\[ x = 15.96 \]
Thus, the original price of the shirt is \($15.96\).