How do I interpret this?

This means the limit of f(x) as x approaches 2 from below.

In the function graphed below we see that 

\(\lim \limits_{x\to 2^-} = 1 \\ \lim \limits_{x \to 2^+} = 5 \\ \lim \limits_{x\to 2} \text{ does not exist.}\)