How to stop the dock showing up in other apps?

How do I stop the “dock” from appearing when I am in another app?

Recently I was playing a game on the iPad and mid battle the dock showed up as I was doing something and as I was doing what I needed I accidentally switched to another app costing me and my team the battle. I have tried turning off multitasking but find that even the slightest swipe up guesture brings the dock up again and I want to stop this so it doesn’t happen again in the future.