To find the area of a circle, you can use the formula:
\[ A = \pi r^2 \]
where \( A \) is the area and \( r \) is the radius of the circle. The radius is half of the diameter. Given that the diameter is 18 inches, the radius will be:
\[ r = \frac{18}{2} = 9 , \text{inches} \]
Now plug the radius into the area formula:
\[ A = \pi (9)^2 = \pi (81) \]
Now calculate \( A \):
\[ A \approx 3.14 \times 81 \approx 254.34 , \text{square inches} \]
Rounding to the nearest whole number, the area is:
\[ A \approx 254 , \text{square inches} \]
Thus, the area of the circle is approximately \( \boxed{254} \) square inches.