1. The problem is to find the value of $\lfloor 2.5 \rfloor$. 2. The floor function $\lfloor x \rfloor$ gives the greatest integer less than or equal to $x$. 3. For $x = 2.5$, the greatest integer less than or equal to 2.5 is 2. 4. Therefore, $\lfloor 2.5 \rfloor = 2$. Final answer: $2$