To express the product \( (1/8)(1/8)(1/8) \) in exponential form, we first recognize that multiplying \( \frac{1}{8} \) by itself three times can be represented as \( \left( \frac{1}{8} \right)^3 \).
Next, we can also rewrite \( \frac{1}{8} \) as \( 8^{-1} \). Therefore, we have:
\[ \frac{1}{8} = 8^{-1} \]
Now substituting into our expression:
\[ (1/8)(1/8)(1/8) = \left(8^{-1}\right) \left(8^{-1}\right) \left(8^{-1}\right) = 8^{-1} \times 8^{-1} \times 8^{-1} \]
Using the property of exponents that states \( a^m \times a^n = a^{m+n} \):
\[ 8^{-1} \times 8^{-1} \times 8^{-1} = 8^{-1 - 1 - 1} = 8^{-3} \]
Thus, the exponential form of the expression \( (1/8)(1/8)(1/8) \) is \( 8^{-3} \).
The exponent in this exponential form is:
\[ \boxed{-3} \]