The area between the baseline and the service line. Called no-man's land because standing here means the ball bounces at your feet, making it extremely difficult to hit clean shots. You're too far from the net to volley effectively and too close to the net to hit comfortable groundstrokes. The basic rule: either commit to the baseline or commit to the net. Don't hang out in between.
"She's stuck in no-man's land after a short approach shot and the ball bounces right at her ankles. Forced error."