To find an equivalent expression for \( \frac{1}{8^5} \), we can apply the property of exponents that states:
\[ \frac{1}{a^n} = a^{-n} \]
In this case:
\[ \frac{1}{8^5} = 8^{-5} \]
So, the correct option that matches this is:
8⁻⁵ (8 superscript negative 5 baseline).